The LibreraX Book

The complete guide to LibreraX 1.2.64 for Android and iOS: every screen, option, sort order, field and setting, with screenshots. Read it here, or download it.

The complete guide to LibreraX: every screen, feature, option, sort order, field and setting

LibreraX (iOS, Android)

Version: LibreraX 1.2.63 for Android and iOS
Author: Ivan Ivanenko
Web: librera.app

Edition of 6 November 2026.

About this book

This book describes what LibreraX (iOS, Android) does, as the code does it today. Every label in quotes is the exact English text the app shows, every default is the value the app uses when nothing has been chosen, and every limit is the one the app applies. Where the two platforms differ, the text says so, and each part ends with an Android vs iOS table.

How to read it

• Introduction: what LibreraX is, a map of its features, and how it compares with other readers.
• Parts 1-6: one area of the app each: the library, the reading screen, formats/PDF/notes, reading aloud and other devices, OPDS/cloud/editions, and the full Settings reference.
• Appendix: a glossary of the terms used in the book.

Conventions

What LibreraX is

LibreraX (iOS, Android) is an e-book reader for Android (phones, tablets, Chromebooks, e-ink readers) and iOS/iPadOS (iPhone, iPad, and Macs running the iPad app). Both platforms are built from one Kotlin Multiplatform code base, with the user interface in Compose Multiplatform. It follows the classic Librera Reader: progress, favourites, bookmarks and tags move over from Librera in one step with “Export to LibreraX” (§1.18).

Design principles visible throughout the code:

1. One reader for all reflowable text. EPUB, MOBI/AZW3, FB2, TXT, Markdown, HTML, DOC, DOCX and RTF are all laid out by one shared copy of foliate-js inside the platform’s own WebView. Themes, fonts, CSS, tap zones, notes, search and read-aloud therefore work the same in every format and on both platforms. The same reader plays video and audio built into EPUB 3 books and shows math formulas (MathML) and vector graphics (SVG) (§2.1.1).
2. Native engines for pages. PDF uses PDFium on Android and PDFKit on iOS. Comics (CBZ, CBR) use the same page reader. DjVu opens on Android through an installed Librera PRO.
3. Your files, your folders. The library is built by scanning only the folders the reader chooses in the system’s own secure folder picker (Android’s Storage Access Framework, the Files picker on iOS), or single files added by hand. LibreraX needs no permission to read all files. Nothing is imported into a closed store. Metadata edits are written back into the book file.
4. Your data travels with you. With a Google (or Apple) account, reading positions, bookmarks, notes, favourites, tags and read marks are synced through LibreraX’s cloud. Book files can be kept in the reader’s own Google Drive folder LibreraX/Books.
5. Everything configurable. Tabs, shelves, book actions, tap zones, themes, fonts, status bar, dictionaries and selection tiles can be reordered, renamed, hidden or redefined.

LibreraX in numbers

Feature map

A one-page view of everything in this book, grouped by area. Each line points to the section with the details.

Library and organisation (Part 1)

• Home tabs: Library, Folders, Cloud, OPDS, Notes, Settings. Reorderable and hideable (§1.1).
• Shelves: Library, Reading Now, Recent, Favorites, Unread, Read, My tags (one shelf per tag), Excluded. Renamable, reorderable, swipeable (§1.3).
• Views: List, Two columns, Grid, Covers. Cover size, cover radius, series pennant, format-coloured placeholders (§1.4).
• Groups: by author, author last name, genre, series, keywords, language, tag, publisher, publication year (§1.5).
• 13 sort options with section headers and a fast scrollbar with a section bubble (§1.6, §1.4.4).
• Search across title, author, series, genre and file name, with @field prefixes (§1.7).
• Selection with 12 book actions (§1.8), File info (§1.9), tags/favourites/read marks (§1.10).
• Folder scanning, excluded folders (.nomedia), permission re-grant, file browser (§1.11-§1.13).
• Duplicate hiding by author+title or file name; format filter (§1.14).
• App themes (System, Dark, White, Custom with OLED and E-ink styles), accent colours, sizes (§1.15).
• Metadata editor that writes into EPUB, FB2 and PDF, with cover from the book, a file or a link (§1.16).
• Backup/restore of the whole library and settings; import from Librera (§1.17, §1.18).

Reading (Part 2)

• Top and bottom panels, book strip, seek bar, mode label (§2.3, §2.4).
• 3 × 3 tap zones with 26 actions, gestures, keyboard, mouse wheel, volume keys (§2.5-§2.7).
• Paged or vertical scroll, one or two columns, page animation, text direction (§2.8).
• Full screen, keep-screen-on timer, brightness strip (§2.9, §2.10).
• Status bar: chapter ticks, pages left, clock, battery, page number, or a movable percent label (§2.11).
• Contents, Go to page over rendered previews, Find in book (§2.12-§2.14).
• Reading themes with an editor, WCAG contrast, aged-paper texture, illustrations blended into the page (§2.15, §2.16).
• Typography: 10 font choices, own fonts, size, line spacing, per-side padding, alignment, bold text, hyphenation in 76 languages, user CSS (§2.17-§2.19).
• Inline footnotes, link back-stack (§2.20).
• Selection popup: 7 colours, highlight/underline/strike/note/bookmark, copy, translate, 24 web dictionaries, dictionary apps (§2.21, §2.22).
• Find and replace and highlight rules (§2.23), auto scroll (§2.24), speed reading RSVP (§2.25), accent reading (§2.26).

Formats, PDF, comics and notes (Part 3)

• Format engine matrix, metadata read and written per format (§3.A).
• PDF/DjVu/comic page reader: zoom, fit, crop margins (auto/manual), half/one/two pages, night recolouring, page reflow, Reflow to EPUB (§3.B).
• Drawing and annotations on pages, saving them into the PDF, editing a PDF’s own annotations (§3.B.12-§3.B.15).
• Notes and bookmarks: kinds, colours, the reader’s Bookmarks dialog, the Notes tab, storage and sync (§3.C).

Reading aloud and other devices (Part 4)

• TTS dialog: engine, voice, speed, pitch, sleep timer, pauses, replacement-rule files (§4.3).
• Engine behaviour: what is read, highlighting, automatic page turn, previous/next rules (§4.4).
• Android media session, notification, headset; iOS Now Playing (§4.5, §4.6).
• Home-screen widgets on Android and iOS (§4.7, §4.8). Wear OS and Apple Watch (§4.9). Android Auto and CarPlay (§4.10).
• Automation apps, opening books from other apps, Librera integration, e-ink devices (§4.11-§4.15).

Catalogs, cloud and editions (Part 5)

• OPDS: built-in catalogs, adding with discovery, login, proxy, browsing, search, downloads, “Free books” strip (§5.A).
• Cloud: Google/Apple sign-in, what is synced, conflict rules, Google Drive books, Wi-Fi only, account deletion (§5.B).
• Editions: FREE, PRO 3H, PRO, PRO+; ads, consent, reward-video trial, subscriptions, licences (§5.C).

Settings (Part 6)

• Every Settings card in screen order with its choices and defaults, the interface languages and backup.

Table of contents

• About this book
• What LibreraX is
  • LibreraX in numbers
• Feature map
  • Library and organisation (Part 1)
  • Reading (Part 2)
  • Formats, PDF, comics and notes (Part 3)
  • Reading aloud and other devices (Part 4)
  • Catalogs, cloud and editions (Part 5)
  • Settings (Part 6)
• Comparison with other book readers
• Part 1 — The library
  • 1.1 Home screen and navigation bar
    • 1.1.1 Tabs
    • 1.1.2 Bar styles
    • 1.1.3 Back button behaviour
    • 1.1.4 Full screen
  • 1.2 Library tab — layout overview
    • 1.2.1 Reading Now strip (in the top bar)
    • 1.2.2 Read-aloud header
    • 1.2.3 Title icon = groups toggle
  • 1.3 Shelves (Library tabs)
    • 1.3.1 Shelf list
    • 1.3.2 Long-press on a chip
    • 1.3.3 Lead buttons on the strip
    • 1.3.4 Library tabs settings (Settings → “Library tabs”)
    • 1.3.5 Search interaction with chips
    • 1.3.6 “Free books” strip (Discover)
  • 1.4 Display (view) modes
    • 1.4.1 What each card shows
    • 1.4.2 Page count shown
    • 1.4.3 Section headers
    • 1.4.4 Fast scrollbar
    • 1.4.5 Cover placeholders
  • 1.5 Groups mode (browse by metadata)
    • 1.5.1 Author name parsing
  • 1.6 Sorting
    • 1.6.1 Library sort options (menu order)
  • 1.7 Search
  • 1.8 Selection and book actions
    • 1.8.1 Book actions (default order)
    • 1.8.2 Delete dialog
    • 1.8.3 Opening a book whose file is gone
  • 1.9 File info
    • 1.9.1 Window
    • 1.9.2 Header
    • 1.9.3 Fields (shown only when not empty, in this order)
  • 1.10 Tags, favourites, read marks
    • 1.10.1 Tags editor (“My tags”)
    • 1.10.2 Favourites
    • 1.10.3 Read marks
    • 1.10.4 Marks shared between copies
  • 1.11 Adding books and library folders
    • 1.11.1 Where the buttons are
    • 1.11.2 “Add folders”
    • 1.11.3 “Add books”
    • 1.11.4 Folder permission lost (Android)
  • 1.12 Folders tab (file browser)
    • 1.12.1 Top bar
    • 1.12.2 Selection in the Folders tab
  • 1.13 Scanning
    • 1.13.1 When a scan runs
    • 1.13.2 Which files count
    • 1.13.3 What you see during and after a scan
    • 1.13.4 Metadata sources
    • 1.13.5 Excluded folders
  • 1.14 Duplicates and formats
    • 1.14.1 “Hide duplicates” (Settings → Other settings)
    • 1.14.2 Formats filter
    • 1.14.3 “Hide Cloud books in Library”
  • 1.15 Appearance: themes, sizes, covers
    • 1.15.1 “Theme”
    • 1.15.2 Custom theme
    • 1.15.3 Sizes
    • 1.15.4 Other appearance switches (Settings → “Other settings”)
    • 1.15.5 Covers
  • 1.16 Metadata editor (“Edit metadata”)
  • 1.17 Backup and restore
  • 1.18 Import from Librera (Android only)
  • 1.19 Settings that belong to the library (summary)
  • 1.20 Android vs iOS differences
  • 1.21 Notable details and edge cases
• Part 2 — Reading
  • 2.1 Which books open in the reflowable reader
    • 2.1.1 Video, audio, formulas and vector graphics
  • 2.2 Screen layout at a glance
  • 2.3 Top panel
  • 2.4 Bottom panel (footer)
  • 2.5 Tap zones
    • Default layout
    • All assignable actions
    • Rules
    • The “Tap zones” editor
  • 2.6 Gestures in the page
  • 2.7 Keyboard, mouse wheel and volume keys
    • Keyboard (tablets with a keyboard, Mac running the iPad app)
    • Mouse wheel / trackpad
    • Volume keys (Android only)
  • 2.8 Paged vs scroll, columns, page-turn animation, RTL
    • Paged and Vertical (scroll) modes
    • Two pages (columns)
    • Page-turn animation
    • Reading direction (“Orientation”)
  • 2.9 Full screen, keep screen on
  • 2.10 Brightness
  • 2.11 Status bar and progress display
    • Full bar
    • Percent mode
    • 2.11.1 Configuring the status bar, step by step
    • What “pages” mean in reflowable books
  • 2.12 Table of contents (“Contents”)
  • 2.13 Go to page and the page previews grid
  • 2.14 Search in book (“Find”)
  • 2.15 Reading themes
    • Built-in themes
    • Choosing a theme
    • Themes section (Settings -> “Themes”)
    • Theme editor (“New theme” / “Edit theme”)
    • How themes look in the book
  • 2.16 Paper texture and illustrations
    • 2.16.1 “Paper”
    • 2.16.2 “Replace white in images with page color” (multiply illustrations)
  • 2.17 Typography
    • Font family
    • 2.17.1 Fallback fonts
    • Size, spacing, margins
    • Alignment
    • Bold text
    • Hyphenation
  • 2.18 User fonts
  • 2.19 User CSS
  • 2.20 Footnotes and links
  • 2.21 Text selection and the selection popup
    • Built-in web dictionaries (open in the browser)
    • Installed apps (Android only)
  • 2.22 Highlights, underline, strikethrough, notes, bookmarks
    • “Bookmarks” dialog
  • 2.23 Find and replace rules (“Replace”)
  • 2.24 Auto scroll
  • 2.25 Speed reading (RSVP)
  • 2.26 Accent reading (accent view)
  • 2.27 Relayout pages (PDF only, for reference)
  • 2.28 The reader Settings dialog, complete layout
    • 2.28.1 Window size: double-tap the title
  • 2.29 Global vs per-book
  • 2.30 Platform differences (Android vs iOS)
  • 2.31 Power-user notes
• Part 3 — Formats, PDF and comics, notes and bookmarks
  • 3.A Formats
    • 3.A.1 Master list of extensions
    • 3.A.2 Formats at a glance
    • 3.A.3 Which reader opens which file
    • 3.A.4 Format details and limits
    • 3.A.5 Platform differences (formats)
    • 3.A.6 Metadata writing (“Edit metadata”)
    • 3.A.7 Comic metadata (ComicInfo.xml + file name)
    • 3.A.8 Office file-name metadata
    • 3.A.9 Calibre metadata.opf
    • 3.A.10 Library “Formats” switches
  • 3.B PDF and page-image reader (PDF, DjVu, CBZ, CBR)
    • 3.B.1 Capability matrix by format
    • 3.B.2 Reading modes and the mode button
    • 3.B.3 Page layout menu (bottom panel layout icon)
    • 3.B.4 Zoom and fitting
    • 3.B.5 Crop margins
    • 3.B.6 Gap between pages
    • 3.B.7 Colours: themes, night recolouring, Paper, Bold text
    • 3.B.8 Page previews (“Go to page”)
    • 3.B.9 Text selection (PDF, DjVu)
    • 3.B.10 Reflow pages (in-reader text reflow)
    • 3.B.11 Reflow to EPUB (PDF only)
    • 3.B.12 Annotations on PDF / DjVu / comics — overview
    • 3.B.13 Draw mode and the Draw bar
    • 3.B.14 Saving annotations into the PDF file
    • 3.B.15 Editing annotations already inside a PDF (“PDF editing”)
    • 3.B.16 Comic reading options
    • 3.B.17 Other page-reader details
  • 3.C Notes and bookmarks
    • 3.C.1 What kinds of marks exist
    • 3.C.2 Colours
    • 3.C.3 How marks are drawn
    • 3.C.4 Selection toolbar (both readers)
    • 3.C.5 Bookmarks dialog inside the reader
    • 3.C.6 Bookmarks (Notes) screen — main app tab
    • 3.C.7 Sync
• Part 4 — Reading aloud, widgets, watches, cars and integrations
  • 4.1 Overview
  • 4.2 Where Read Aloud lives in the app
    • 4.2.1 Background reading (leaving the book while it is being read)
  • 4.3 The “TTS” dialog
    • 4.3.1 Overflow menu
    • 4.3.2 First card: voice
    • 4.3.3 Voice picker
    • 4.3.4 Second card: reading behaviour
    • 4.3.5 Sleep timer behaviour
    • 4.3.6 Replacement rules (“Replace” editor)
    • 4.3.7 “Pause after” dialog
    • 4.3.8 On-page TTS buttons
  • 4.4 How reading works (engine behaviour)
    • 4.4.1 What is read
    • 4.4.2 Highlighting and following the voice
    • 4.4.3 Automatic page/chapter turn
    • 4.4.4 Previous / next semantics (important difference between controls)
    • 4.4.5 Resume
  • 4.5 Android media session, notification and headset
    • 4.5.1 Notification
    • 4.5.2 Media session (lock screen, quick settings media player, Bluetooth, car)
    • 4.5.3 Headset and media keys
    • 4.5.4 Audio focus
    • 4.5.5 “Last-read book”
  • 4.6 iOS Now Playing, lock screen and remote commands
  • 4.7 Android home-screen widgets
    • 4.7.1 Shelf widget
    • 4.7.2 Book widget
    • 4.7.3 Read-aloud (TTS) widget
  • 4.8 iOS home-screen widgets
  • 4.9 Watch apps
    • 4.9.1 Wear OS (Android)
    • 4.9.2 Apple Watch
  • 4.10 Cars
    • 4.10.1 Android Auto (PRO edition only)
    • 4.10.2 CarPlay (iOS)
  • 4.11 Automation (Android)
  • 4.12 Opening books from other apps, “Open with” and sending
    • 4.12.1 Android: LibreraX as a book viewer
    • 4.12.2 iOS: document types and URL scheme
    • 4.12.3 “Open with” and “Send file”
  • 4.13 Integration with Librera (the classic app)
    • 4.13.1 Librera’s “LibreraX reading mode”
    • 4.13.2 Librera’s “Export to LibreraX”
  • 4.14 E-ink devices
  • 4.15 App-wide animation speed
  • 4.16 Settings reference (TTS and devices)
  • 4.17 Platform differences at a glance
• Part 5 — OPDS catalogs, cloud sync and editions
  • 5.A OPDS catalogs
    • 5.A.1 Where OPDS lives in the app
    • 5.A.2 Built-in catalogs
    • 5.A.3 Catalog list screen
    • 5.A.4 Adding / editing a catalog
    • 5.A.5 Browsing a catalog
    • 5.A.6 Search
    • 5.A.7 Login / authentication
    • 5.A.8 Proxy server (OPDS only)
    • 5.A.9 Page menu (inside a catalog)
    • 5.A.10 Book details sheet
    • 5.A.11 Downloads
    • 5.A.12 “Free books” strip (Discover / popular books)
    • 5.A.13 OPDS preferences summary
  • 5.B Cloud and sync
    • 5.B.1 Overview
    • 5.B.2 Where the account is managed
    • 5.B.3 Sign-in methods and platform differences
    • 5.B.4 What is synced
    • 5.B.5 How syncing works
    • 5.B.6 When syncing happens
    • 5.B.7 Google Drive — LibreraX/Books
    • 5.B.8 “What is synced” dialog
    • 5.B.9 Cloud screen layout
    • 5.B.10 Use only Wi-Fi
    • 5.B.11 Account deletion
    • 5.B.12 Sign out
    • 5.B.13 Cloud and sync preferences summary
  • 5.C Editions and monetisation
    • 5.C.1 The four statuses
    • 5.C.2 What PRO unlocks (paid features)
    • 5.C.3 Advertising (AdMob)
    • 5.C.4 Consent (UMP) and tracking (ATT)
    • 5.C.5 Reward video trial
    • 5.C.6 Subscriptions
    • 5.C.7 Cross-platform subscription (through the account)
    • 5.C.8 Subscription message (offer card)
    • 5.C.9 In-app update of LibreraX PRO (Android PRO app only)
    • 5.C.10 App review prompts
    • 5.C.11 Licenses screen and third-party list
    • 5.C.12 Privacy-relevant facts
• Part 6 — Settings reference
  • 6.0 Order of the screen at a glance
  • 6.1 Top bar
  • 6.2 “Folders to Scan”
  • 6.3 “Excluded folders”
  • 6.4 “Library N” and format switches
  • 6.5 “Google account” (cloud sync)
  • 6.6 “Theme”
    • Built-in palettes
    • “Custom” sub-settings (shown only when “Custom” is selected)
  • 6.7 “Controls size”
  • 6.8 “Cover size”
  • 6.9 “Cover radius”
  • 6.10 “Font size” (app UI text)
  • 6.11 “Navigation bar” (home tabs)
  • 6.12 “Library tabs” (shelves)
  • 6.13 “Book actions”
  • 6.14 “Other settings”
  • 6.15 “Backup”
  • 6.16 “Language”
    • Languages offered in the menu (in this order)
  • 6.17 “About”
• Appendix — Glossary

Comparison with other book readers

The other apps’ columns come from their public feature lists and common knowledge as of late 2026. They change often and some features need a paid tier, so treat this table as a guide and check before quoting it. Legend: ✅ yes · 🟡 partial, via a plugin, or paid only · ❌ no

Platforms and business model

Formats

Reading and library features

Where LibreraX stands out

• One code base on Android and iOS. The same library, reader, themes and settings on phone and tablet on both systems. Classic Librera, Moon+ Reader and KOReader don’t run on iOS.
• One rendering engine for every reflowable format. EPUB, MOBI, AZW3, FB2, TXT, Markdown, HTML, DOC, DOCX and RTF all go through the same foliate-js page, so themes, fonts, CSS, tap zones, notes and TTS behave the same in every format.
• A library tool, not just a shelf. Nine groupings, thirteen sort options, duplicate hiding, the reader’s own tags as shelves, a metadata editor that writes back into EPUB, FB2 and PDF, and a fast scrollbar for libraries with thousands of books.
• Reading aloud everywhere. In the app, from the notification, lock screen, headset, home-screen widgets, Wear OS and Apple Watch (CarPlay is wired up in development builds), with replacement rules kept in files.
• Speed reading (RSVP) built into the reader. Mainstream readers rarely have it.
• A clean move from Librera. In Librera, left menu → Backup → “Export to LibreraX” moves positions, bookmarks, tags and favourites across in one step (§1.18).

Where others are ahead

• DjVu: ReadEra, KOReader, PocketBook and classic Librera open DjVu on their own. LibreraX needs Librera PRO installed on Android and doesn’t open DjVu on iOS.
• CHM, ODT, XPS, EPUB3 media overlays: some competitors support these. LibreraX doesn’t.
• Desktop and web: KOReader, FBReader, Readest and the store apps also run on computers.
• Store ecosystems: Apple Books, Play Books and Kindle come with a bookstore, audiobooks and publisher DRM. LibreraX reads DRM-free files only.
• Open source: KOReader, Readest and classic Librera are open source. LibreraX is closed source.

Part 1 — The library

Everything around the book collection: the home screen and its tabs, shelves, views, groups, sorting, search, book actions, File info, tags, scanning, the Folders browser, duplicates, app appearance, the metadata editor, backup and the Librera import.

1.1 Home screen and navigation bar

1.1.1 Tabs

• Default order is the order above. Order and visibility are changed in Settings → “Navigation bar” (a drag-to-reorder list with a drag handle on the left and a switch on the right; the Library and Settings switches are disabled). LibreraX remembers your choice. Tabs added in future versions appear at the end.
• Opening OPDS from the Library (long-press on the “OPDS” pill) automatically un-hides the OPDS tab.
• The Cloud tab shows a thin progress bar under its icon while a Drive upload or download is running.
• The app opens on the Library tab. Each tab keeps its own state (scroll position and so on) while you switch.

1.1.2 Bar styles

• Floating pill bar (default on Android, and on iOS when “System components” is off): a rounded panel floating above the bottom edge, with a gradient behind it; the selected tab is highlighted with an accent “patch”.
• Square band: when Cover radius = “0” the bar becomes a flat full-width band with no rounded patch and no ripple (the whole app chrome turns square).
• Native iOS tab bar (“Liquid Glass”): only on iOS 26 or newer, and only while Settings → Other settings → “System components” is on (default on). Subtitle: “Native iOS navigation bar and buttons with Liquid Glass”. The same switch turns top-bar buttons, the search field, switches and menus into native glass controls.

1.1.3 Back button behaviour

• On any tab other than Library: Back returns to Library.
• On Library: Back may first show the store review prompt, then leaves the app.
• Inside the Library: Back clears a selection first, then closes the groups bar, then closes the embedded OPDS view.
• Tapping the title (app name + icon) on Folders / Cloud / OPDS / Notes / Settings returns to Library.

1.1.4 Full screen

• Settings → Other settings → “Full screen” (switch, default off): hides the system status and navigation bars on the library, folders and settings screens. It is applied again every time you return to the app.

1.2 Library tab — layout overview

From top to bottom:

1. Top bar: “LibreraX” title + icon (the icon is a button), the Reading Now cover strip, then three action buttons: Search (magnifier), Display picker, Sort picker.
2. Search field (when opened), placeholder “Find”.
3. Shelf strip: optional lead buttons (“+” Add, “OPDS” pill) followed by shelf chips with counts; or, in groups mode, the group-mode chips.
4. A moving progress line while a scan (or an OPDS fetch) is running.
5. Banners: backup-restored notice, folders-need-access list, “Free books” strip (empty library).
6. The book list for the selected shelf; shelves are pages you can swipe left/right.

The top bar collapses when you scroll down and comes back when you scroll up (not on iPad, where it stays). While books are selected the bar is always shown.

1.2.1 Reading Now strip (in the top bar)

• Shows covers of books on the Reading Now shelf (up to 12, as many as fit; the covers shrink so that at least two fit on a narrow phone). Tap a cover to open the book.
• Only shown when at least one book is being read and nothing is selected.

1.2.2 Read-aloud header

• While background read-aloud (TTS) is active, the title icon turns into headphones and a play/pause button appears. Tapping the headphones icon hides this header (instead of opening groups).

1.2.3 Title icon = groups toggle

• Tapping the LibreraX mark next to the title switches the strip into groups mode (see §1.5). In groups mode the icon shows the current group mode’s icon; tapping it again (or Back) returns to the shelves.

1.3 Shelves (Library tabs)

1.3.1 Shelf list

• Each chip shows a count badge (hidden when 0). Counts follow the current search text and the format filter.
• Default order: Library, Reading Now, Recent, Favorites, Unread, Read, My tags, Excluded. None hidden by default.
• The shelf shown at launch is the first visible shelf in your order.
• Swiping the list horizontally moves to the next/previous shelf; the chip strip scrolls to keep the selected chip in view.
• Shelves other than Library/Unread show books even when they are not in a library folder (for example a book opened from another app), as long as the book is not excluded and its file is not missing.
• Recent and Reading Now always ignore the Sort setting and show no section headers.

1.3.2 Long-press on a chip

Not available with the iOS native segmented control (System components), which only switches shelves.

1.3.3 Lead buttons on the strip

• ”+” (Add): circle button before the chips; opens the Add menu (storage sources + “Add books”). Turned on or off in Settings → “Library tabs” → “Add books” switch (default on).
• “OPDS” pill: tap = shows the “popular books” OPDS page embedded inside the Library (Back closes it); long-press = switches to the OPDS tab (and un-hides it). Turned on or off in Settings → “Library tabs” → “OPDS” switch (default on; turning it off also unpins the “Free books” strip).

1.3.4 Library tabs settings (Settings → “Library tabs”)

• Two switches: “Add books” and “OPDS” (above).
• Reorderable list of shelves with a drag handle, an edit (pencil) button and a show/hide switch.
• Rename: every shelf except “My tags” can be renamed. The dialog title is the default name; a text field (the Done key saves); buttons “Save”, “Reset” (only when a custom name exists), “Cancel”. Saving the default name or an empty name removes the custom name.
• You cannot hide the last visible shelf.
• Order, hidden shelves and custom names are remembered.

1.3.5 Search interaction with chips

• While search text is entered, chips whose count is 0 disappear (except “Library” and the chip you are on).

1.3.6 “Free books” strip (Discover)

• On the Library shelf (no tag) a header row “Free books” (or the title of the pinned OPDS page) with a horizontal row of OPDS covers can appear above the books; it is also shown when the library is empty. Tap the title to open the embedded catalog; tap a cover to open its book sheet.
• On by default (default page: Project Gutenberg popular). It is controlled from the OPDS screen (“Show on library screen”).

1.4 Display (view) modes

The top bar Display button (icon = current mode) opens a menu with a check on the current mode.

• Library default: Grid. The Folders tab has its own setting (see §1.12).
• The number of columns for Grid/Covers depends on the Cover size setting (§1.15.3) and screen width; Two columns is always 2.
• In the free (ad-supported) edition an ad row appears every 32 books.

1.4.1 What each card shows

• Author line = Author (Series, N); if no author: Series, N; if no series: the author. If the author is empty and there is no series, the parent folder name in brackets is shown instead, e.g. [Downloads].
• Info text parts (separated by two spaces, each only when known): reading progress %, file extension in capitals, file size with page count in parentheses (2.4 MB (312), or (≈312) when estimated), file modified date (in the chosen Date format).
• Cloud mark: filled cloud = the book is in the Cloud and on this device; outline cloud = “In the Cloud, not on this device”.
• Series pennant: when the book has a number in a series, a small accent-coloured flag with the number is drawn at the top-left of the cover (all views, File info too).
• Selected books are tinted with the accent colour.
• Size units: B, kB, MB, GB, TB (decimal, one decimal place).

1.4.2 Page count shown

• PDF/DjVu/comics (fixed layout): pages from the file, or the reader’s count.
• Reflowable books (EPUB, MOBI, FB2, TXT…): the reader’s page count once the book has been opened; before that an estimate prefixed with “≈”.

1.4.3 Section headers

When sorted by these orders (not on Recent / Reading Now), headers are inserted:

Missing dates are grouped under “No date”; names beginning with a non-letter go under “#”.

1.4.4 Fast scrollbar

• A thin thumb at the right edge. Always visible on tablets; on phones it appears while scrolling and fades just under a second after scrolling stops.
• Drag the thumb to jump; it widens and turns accent while held.
• When the list has section headers, a bubble next to the thumb shows the current section (year / letter).
• Tapping a list that is still flinging only stops it (it does not open the book under your finger).

1.4.5 Cover placeholders

• Used when a book has no cover, or when “Show book covers” is off.
• A coloured gradient per format with a book-spine stripe: PDF red, EPUB green, MOBI/AZW orange, FB2 blue, DjVu purple, CBZ/CBR teal, TXT/MD grey-blue, HTML/XHTML indigo, DOC/DOCX/RTF brown, ZIP grey, other slate.
• Shows the title (serif bold, up to 5 lines), a short rule, the author (2 lines) and a format badge (e.g. “FB2”, “DJVU”). Very small covers show only the format label.

1.5 Groups mode (browse by metadata)

Open: tap the LibreraX icon in the top bar. The strip then shows group-mode chips; swipe left/right to change mode.

• The first time you open groups, Author is selected; afterwards the last mode is remembered.
• Each group row: an accent circle with its first letter, the group name, and the number of books. Groups are sorted alphabetically, ignoring case; names that differ only in case are merged (“tolkien” and “Tolkien”).
• Tap a group to unfold it; its books appear below in the current Display mode, sorted by the current Sort. Several groups can be open at once. Tap again to fold.
• Long-press a book inside a group to start selection; taps then toggle selection.
• Group counts honour the format filter, “Hide duplicates” and “Hide Cloud books in Library”.
• Search in groups mode filters group names; each mode chip then shows how many groups match (updated shortly after you stop typing).
• Jumping from File info: tapping an Author, Series, Genre, Keywords, Language, Publisher or Publication Date value opens the Library in the matching groups mode with that group unfolded and scrolled into view.

1.5.1 Author name parsing

• Several authors in one field are separated by ;, &, or the words “and”, “и”, “і”.
• Last, First is recognised (also Last1, First1, Last2, First2).
• The last name skips initials (e.g. “J.” or “J.R.R.”), suffixes (Jr, Sr, II, III, IV, PhD, MD), and keeps a capitalised particle with it (“Le”, “La”, “De”, “Da”, “Di”, “Du”, “Del”, “Della”, “Van”, “Von”, “Mac”).

1.6 Sorting

The Sort button’s icon shows the direction. Its menu: the first row is the current sort with an up/down chevron (tap it to flip ascending/descending), a divider, then the options (the current one checked). Long-press the Sort button to flip the direction directly (non-glass style).

1.6.1 Library sort options (menu order)

• Direction: default descending. The sort and its direction are remembered.
• Books that tie are ordered by title ascending (except in the Title sort); Series also uses the number in series, Author last name also uses the author.
• While searching with the “Author last name” sort, only the authors that match the search words are used to place a book.

1.7 Search

• Tap the magnifier to open the search field (“Find”); tap again to close and clear it. An × in the field clears the text.
• Search applies to the current shelf and updates the shelf counts.
• Fields searched: Title, Author, Series, Genre, File name.
• Matching: the text is split into words (punctuation , ; : . " ' ( ) « » is trimmed); every word must match. A word matches when a word in one of the five fields starts with it, or when it appears anywhere inside one of the fields (ignoring case).
• Field-prefix syntax (for power users, typed into the search box):

@author Tolkien = contains; @author "J. R. R. Tolkien" (in quotes) = exact name. Quoted values for series/language/year/publisher match the whole field exactly (ignoring case). A tag search shows tagged books regardless of the format filter.

1.8 Selection and book actions

• Tap a book = open it. Long-press = select it and enter selection mode; taps then toggle selection.
• The top bar shows × (clear selection) and the number selected. The first 4 visible book actions become icons on the bar; a ⋮ menu holds all visible actions.

1.8.1 Book actions (default order)

• By default the bar icons are Info, My tags, Add to favorites, Remove from favorites.
• Settings → “Book actions”: reorder (drag) and show/hide each action. Your order is remembered. Actions added in future versions appear right after the action that comes before them.
• The same action list (minus the selection-only ones) is the book menu inside the reader.
• Exclude takes every copy the card stands for: the same file elsewhere, and — with Hide duplicates — every copy with the same author+title (or file name).
• “Open with”: Android = system app chooser; iOS = share sheet.

1.8.2 Delete dialog

• Title “Delete N”. Text “Delete from the device? The files cannot be brought back.”
• Shows up to 6 covers with file names (“…” when more); a cloud icon marks books also in the Cloud.
• If any selected book is in the Cloud: checkbox “Also delete from the Cloud (to Google Drive trash)” (off by default).
• Buttons “Delete” (red) / “Cancel”.
• Deleting removes the file and everything saved for it: progress, heart, read mark, tags, bookmarks and annotations.

1.8.3 Opening a book whose file is gone

• Unsupported extension: message “EXT: not supported”.
• File moved/deleted or folder permission lost: a file picker opens near the old location. If you pick a file with the same name, the library relinks the book: progress, heart, recent, read mark, tags, bookmarks and annotations move to the new file and the old entry is removed. A file with a different name is just opened.
• Messages: “This book can no longer be opened: its file was moved or deleted, or its folder needs access again.” / “This book was opened from another app, which no longer lets LibreraX read it. Open it from that app again, or add its folder to the library.”

1.9 File info

Open: selection → “Info”; also from the reader and the Notes/Cloud screens.

1.9.1 Window

• Title “File info” (or “Edit metadata” while editing). The popup can be dragged by its title bar, resized from the two bottom corners, and double-tapping the title resets it to its default place or, if it is already there, fills the screen. Size and position are remembered per popup.
• Title-bar icons: pencil (Edit metadata — only EPUB, FB2, FB2.ZIP, PDF), ⋮ menu, × close.
• ⋮ menu: “Edit metadata” (when editable), “Update metadata”, “Add widget to home screen” (Android, only when the launcher supports pinned widgets).
• With several books selected: a row of small covers at the top (the current one outlined); swipe or tap a cover to switch pages.

1.9.2 Header

• Cover (tap = full-size cover, tap again to go back) with series pennant.
• Title (bold, up to 4 lines).
• Heart toggle, read-check toggle (green), a tag icon (only when the book has no tags) to add tags, a widget icon (Android, when supported), and the file extension.
• Tags as accent chips; tap any to edit tags.

1.9.3 Fields (shown only when not empty, in this order)

• Below a divider: “Annotation” — the book description, with bold, italic, underline, headings, paragraphs and line breaks.

1.10 Tags, favourites, read marks

1.10.1 Tags editor (“My tags”)

• Text field with placeholder “tag, another tag” — tags are comma-separated, trimmed, duplicates removed.
• “Apply” appears when the text has changed; the Done key and closing the popup also apply.
• All existing tags appear as chips below; tap a chip to add/remove it (applies immediately).
• One book: the field replaces the book’s tags.
• Several books: the field adds tags to all of them (never removes). The title bar shows an “ALL” chip and a row of covers: tap a cover to edit just that book’s own tags; tap “ALL” to go back.
• Tagging from the Folders tab also puts the book into the library.
• Delete a tag everywhere: long-press its chip on the shelf strip → “Delete tag”.
• Setting tags also updates the book’s “last read” time.

1.10.2 Favourites

• Toggle the heart from the action list, File info, or the reader. Adding a heart also updates the “last read” time. “Clear favorites” (long-press the chip) removes all hearts.

1.10.3 Read marks

• Set by “Mark as read”/”Mark as unread”, the File info check, the Folders folder menu, and automatically by the reader when you reach 99 % or the last page (once per opening, only if the book is not already read).
• Marking a book read/unread by hand removes it from Reading Now until you open it again.

1.10.4 Marks shared between copies

• Heart, last-read time, progress/position and read mark — and tags — are copied to every other library book with the same file name when changed. The recent list, the library/excluded state and the Cloud link stay per file.
• Copies with identical content are always shown as one card.

1.11 Adding books and library folders

1.11.1 Where the buttons are

• Empty library (not signed in, nothing readable or nothing found yet): centred “Add folders” and “Add books” buttons.
• ”+” lead button on the shelf strip, and long-press on the “Library” chip.
• Settings → “Folders to Scan” card: “Add folders” / “Add books”.
• Folders tab root: “Add folders”.

1.11.2 “Add folders”

Private by design. LibreraX never asks for access to all your files. On Android it uses the system folder picker (the Storage Access Framework): you choose a folder, Android asks you to allow it, and LibreraX can read only that folder and what is inside it. On iOS the system picker works the same way. Only the folders you picked, and books you added one by one, appear in the library. Nothing else on the device is scanned, and you can remove a folder in Settings at any time, which also gives its permission back.

• Android: a menu of storage sources — each storage volume (internal storage = phone icon, SD card = card icon), “Downloads”, then cloud document providers (Google Drive per account, plus any provider you allowed before). The system folder picker opens at that place, with all storage shown. The app keeps permission to read the folder (and to write, if allowed). Then a scan starts.
• iOS: the system folder picker opens directly (no source menu). The app keeps access to the folder across restarts.
• The folder list is sorted alphabetically (ignoring case); a folder added twice appears once.
• On Android only folders picked in the system folder picker and the app’s own folders can be library folders.
• On iOS the app’s Documents/Books folder is added automatically at every start (and hidden from the Settings list).

1.11.3 “Add books”

• Android: the system multi-file picker (opens in Download, any file type). Each file is added in place (no copy), and the app keeps permission to read it.
• iOS: document picker with multiple selection; files are copied into Documents/Books (name clashes become name (1).ext, name (2).ext…).
• Unsupported files and ZIPs that contain no book are skipped; message “%1$d of %2$d added: the others are not books the app can open”.
• Books added this way stay on the Library shelf even though no scan finds them.

1.11.4 Folder permission lost (Android)

• Banner at the top of the Library: “Android no longer lets the app read these folders. This happens after the app is reinstalled or restored from a backup. Tap a folder to give access again.” Each folder: name, location — “tap to give access again”. Tapping opens the folder picker; giving access again starts a scan.
• In Settings the folder row is greyed with the same hint; tapping it re-opens the picker.

1.12 Folders tab (file browser)

• The root “/” lists the folders you added (Android). Tap a folder to enter it; levels are pages you can swipe; a breadcrumb strip (“/ › Folder › Sub”) lets you jump to any level; Back goes up one level.
• The current path, the scroll position and unfolded folders are remembered across launches. If the top folder is no longer added, the tab returns to “/”.
• Settings → “Folders to Scan”: tapping a folder row jumps to it in the Folders tab.
• On iOS the tab is hidden by default and has nothing to list, so it shows just the “Add folders” button.

1.12.1 Top bar

• Search: filters names in the current level.
• Display picker: “List”, “Two columns”, “Grid”, “Covers” (its own setting; default = the Library’s display if you ever set it, otherwise Two columns).
• Sort: “Filename”, “File modified date”, “File Size” (default File modified date, descending; remembered). Folders are always listed before files, each sorted the same way.
• ⋮ view menu (check items):

• Without “Show all files”, folders with no books (looked up to 6 levels deep) are hidden.
• Excluded folders (with a .nomedia file) show a crossed folder icon in grey.

1.12.2 Selection in the Folders tab

• Long-press a file: the same selection actions as the Library (§1.8). Hearting or tagging here also adds the book to the library; “Exclude/Include in library” toggles whether it is in the library.
• Long-press a folder: folder ⋮ menu — “Mark as read”, “Mark as unread” (every library book under it), and “Exclude from library” / “Include in library” (creates/deletes a .nomedia file in the folder, then rescans).
• Ctrl/Cmd+C with a hardware keyboard copies the names of the selected items.

1.13 Scanning

1.13.1 When a scan runs

• When you add a folder, remove folders, give access to a folder again, include an excluded folder, or exclude a folder in the Folders tab.
• When you tap “Rescan” in Settings → “Folders to Scan” (the free edition may show an ad first).
• When you open the Library and nothing has been found yet but folders exist, and once after an app update that changes how book details are stored.
• When you switch “Calibre metadata.opf” on or off.
• iOS: at every app start.
• On Android the scan keeps running if you leave the app. If you ask for a scan while one is running, another runs right after it.

1.13.2 Which files count

• Extensions: pdf, epub, mobi, azw, azw3, kf8, prc, fb2, fb2.zip, cbz, cbr, txt, md, html, xhtml, doc, docx, rtf, zip, djvu, djv.
• A .zip counts only when it contains a book.
• Skipped: any folder containing a .nomedia file, with everything under it (it is listed under “Excluded folders”); names starting with “.”; folders named android, .thumbnails and lost+found.

1.13.3 What you see during and after a scan

• New books appear as they are found, first titled with the file name, so the library fills while scanning; titles, authors and covers fill in as each book is read.
• A book whose file changed (size or date) has its details read again.
• A file that was moved or deleted leaves the Library shelf but keeps its progress, heart, read mark and tags; if it comes back at the same place, it is restored with all of them. A moved file can also be relinked by opening it (§1.8.3).
• Books added by hand that can no longer be read are hidden from all shelves as missing until they become readable again.
• Gone files with nothing saved (no progress, heart, tags, bookmarks or annotations) are forgotten.
• A file that made reading its details fail before is skipped on later scans.
• Progress: a moving line under the Library top bar; in Settings the “Library N” card shows a progress bar (files read / total) and a spinning refresh icon in the top bar.

1.13.4 Metadata sources

• Details come from the book file. DOC/DOCX/RTF: title, author and year are taken from the file name. Comics: the book’s details combined with the file name.
• “Calibre metadata.opf” (Settings → Other settings, switch, default off): when a metadata.opf is in the book’s folder, its fields override the book’s own (the page count still comes from the book). Switching it re-reads the affected books.
• Fallbacks: title = file name without extension; creation date = the book’s creation date, else the publication date, else the year.

1.13.5 Excluded folders

• Settings shows an “Excluded folders” card when any exist. Long-press to select, then the + icon in the top bar includes them again (deletes .nomedia) and rescans.

1.14 Duplicates and formats

1.14.1 “Hide duplicates” (Settings → Other settings)

• Switch, default on. Tap the label to choose the rule (choosing a rule also turns it on):

• Applies to every shelf, the counts, tag counts and group counts. Books in the app’s Reflow folder are never merged.
• Independent of this switch, copies with identical content are always one card.

1.14.2 Formats filter

• Settings → “Library N” card: switches in two columns — “PDF”, “EPUB”, “MOBI/AZW”, “DOC/DOCX/RTF” | “FB2”, “TXT/MD/HTML”, “CBZ/CBR”, “DJVU”. All on by default.
• DJVU (Android only): needs Librera PRO 9.6 or newer; otherwise it shows “with Librera PRO” (or “Update Librera PRO”) and tapping opens a sheet “Librera PRO - DJVU” with “Install Librera PRO”/”Update Librera PRO”. Hidden on iOS.
• The last remaining format group cannot be switched off. ZIP is always kept.
• The filter applies to the Library and Unread shelves and to groups — not to Recent, Reading Now, Favorites, Read, Excluded or tag shelves.

1.14.3 “Hide Cloud books in Library”

• Cloud tab setting (default on): books in the Cloud download folder are left out of the Library and Unread shelves and groups (still shown in tag shelves).

1.15 Appearance: themes, sizes, covers

All under Settings, each in a folding section.

1.15.1 “Theme”

Chips: “System”, “Dark”, “White”, “Custom”.

• The old stand-alone OLED theme is converted automatically into Custom → OLED style.
• The first start on an e-ink device begins in Custom → E-ink, unless a theme was chosen before.

1.15.2 Custom theme

• “Theme style” chips: “Dark”, “White”, “OLED”, “E-ink”.
  • OLED = pure black panels, white accent, no panel transparency.
  • E-ink = white panels, black accent, no transparency; turns animations off and sets the reader’s page theme to the first (plain day) theme. Choosing another style turns animations back on.
• “Theme color”: dark styles offer blue-grey, charcoal, indigo, forest green, maroon, brown, deep blue and black; white styles offer white, sepia, light blue, light green, light pink, light yellow and lavender; plus a rainbow swatch for any colour.
• “Accent color”: light blue, green, teal, amber, orange, pink, purple, black and white, plus a rainbow swatch.
• Colour dialog: preview square, colour code field, “Hue”, “Saturation”, “Brightness” sliders, “Apply”/”Cancel” (changes preview live; Cancel restores).
• “Panel transparency N%”: slider 0–70 % (panels from fully opaque to 30 % opaque). Default 8 %.
• The background follows the theme colour (darker for dark styles, lighter for white); the text colour follows the style.

1.15.3 Sizes

1.15.4 Other appearance switches (Settings → “Other settings”)

1.15.5 Covers

• Covers are taken once from each book and kept; PDF and other page-based formats use the first page.
• “Update metadata” or saving metadata replaces the kept cover. Restoring a backup re-creates all covers.

1.16 Metadata editor (“Edit metadata”)

• Available for EPUB, FB2, FB2.ZIP, PDF. Open from File info (pencil or ⋮ → “Edit metadata”).
• Note shown: “Saving writes these fields into the book file itself.”
• Save with the disk icon in the title bar or the “Save” button; “Cancel” discards. A spinner shows while writing.

• Keywords cannot be edited here.
• After saving, the cover and book details in the library are refreshed from the file.
• PRO gate: in the free edition saving first plays a short rewarded video, which unlocks PRO for 3 hours (“Applying this plays a short video first, then everything is open for 3 hours. Subscribe for … to skip the video.”).
• Errors (red): “the book file is not reachable”, “the picture could not be read”, “nothing could be fetched from that link”, or the error message from writing the file.

1.17 Backup and restore

• Settings → “Backup” card: “Export” and “Import”.
• Export: saves the whole library, with all your settings, to a file you choose, named librerax_db10_YYYY-MM-DD-HHMM.db. Message “Export” when done. Android: save-as dialog; iOS: export picker.
• Import: pick a file → dialog “Import” — “Importing replaces the whole library and restarts the app.” → “Import”/”Cancel”.
  • The file must be a LibreraX library backup (“that file is not a library”) from this version of the app or one it can upgrade (“that library was made by another version of the app (X against Y)”).
  • Replaces the library, re-creates covers, restores the settings contained in the backup (values that belong to this device — subscription, trial, launch counters and install id — are kept), then restarts (Android: the app restarts; iOS: returns to the library).
  • Afterwards a banner: “The library is back from the backup, with your settings. Android does not hand the folder permissions over with it: give the app access to your book folders again below.” (× dismisses), together with the folders-need-access list on Android.
• Backed up: books, progress, hearts, recent, read marks, tags, bookmarks, annotations, the library folders list, all settings. Not backed up: the book files, covers, folder permissions (Android).

1.18 Import from Librera (Android only)

Moving from Librera Reader (or Librera PRO)? Your reading progress, favourites, bookmarks and tags come across in one step, so you can carry on in LibreraX where you stopped in Librera.

How to move your data:

1. Install LibreraX on the same phone as Librera.
2. In Librera, open the left menu (Preferences) and scroll to the “BACKUP” section.
3. Tap “Export to LibreraX”.
4. In the “EXPORT TO LIBRERAX” dialog, choose what to move: “Book progress”, “Favorites”, “Bookmarks” and “Tags” (all are ticked by default). Tap “EXPORT”.
5. LibreraX opens, shows “Export progress” with a progress bar, then opens the library with your data in it.

You can export again later; positions are only replaced when Librera’s are newer, and nothing is added twice.

• LibreraX accepts the export only from a Librera app.
• If Librera sends a named profile, that one is used; otherwise the first one.
• What is imported, matched to books by file name (ignoring case):

1.19 Settings that belong to the library (summary)

1.20 Android vs iOS differences

1.21 Notable details and edge cases

• Your shelf, sort, sort direction, display and group mode choices are remembered.
• Opening groups from File info works from any screen: the app switches to the Library tab, selects the group mode and scrolls to the group.
• A book appears on Favorites/Recent/Read/tag shelves even if it lives outside your library folders, but never if it is excluded or its file is missing.
• Excluding a duplicate card excludes all of its copies; including from the Excluded shelf brings them all back.
• When a scanned file disappears it drops out of “Library” but keeps its progress, heart and tags; if it comes back (same place) everything is there again.
• The “Library N” number in Settings counts with the current format filter and duplicate rule.
• Books added by hand that are no longer readable are hidden as missing until they become readable again.
• Popups (File info, tags, settings dialogs) remember their size and position; double-tap the title to reset/maximise.
• The “Last read” time also changes when you heart a book or change its tags.
• Removing a folder from “Folders to Scan” gives up the app’s access to it on Android and rescans (its books leave the Library shelf).

Part 2 — Reading

Everything on screen while a book is open. The main subject is reflowable books (EPUB, MOBI/AZW3, FB2, TXT/MD/HTML, DOC/DOCX/RTF), laid out by foliate-js in the platform WebView. The panels, tap zones, keys, status bar, themes and most dialogs are shared with PDF, DjVu and comics.

2.1 Which books open in the reflowable reader

CBZ/CBR comics, PDF and DjVu use the page reader instead, but share the screens described here. When an HTML page is opened, anything that would run code, load another page or navigate away is removed first (the page is read, not run).

2.1.1 Video, audio, formulas and vector graphics

EPUB 3 books can carry more than text and pictures, and LibreraX shows them inside the page:

These parts are part of the book itself, so read-aloud skips them and the theme colours apply only to the text around them.

2.2 Screen layout at a glance

• Page area: the book, edge to edge, with the reader’s padding and the status bar space kept clear.
• Panels (menu): a top panel and a bottom panel (footer) that appear and disappear together. They are shown when a book opens. A tap in the “Show / hide menu” zone toggles them. Any tap while they are shown just hides them. Page turns, keys and settings changes also hide them.
• Status bar / percent: drawn over the page when the panels are hidden (the full bar is also hidden while the panels are shown).
• Brightness strip: an invisible strip along the left edge (on by default).
• Badges: a short dark badge in the middle of the screen after some actions (font size, theme name, font name, brightness %, auto-scroll speed, text selection on/off). It stays for about 1.2 seconds.
• A spinner shows until the book has opened and moved to its saved place. Errors show in red in the middle.

On iOS 26 and later, when the app’s native tab bar setting is on, the panels, buttons, sliders and menus use native “glass” components. The functions are the same.

2.3 Top panel

Book line (centre):

Icon row (left to right):

2.4 Bottom panel (footer)

From top to bottom:

1. TTS transport (only while read-aloud is speaking or paused): previous / play-pause / next. Pressing a button hides the panels. A “PRO” tag may show next to it in the FREE edition.
2. Book strip (toggled by the first footer icon, remembered): a row of shelf chips and up to 40 covers.
   • Chips: “Library N”, “Recent N”, “Favorites N”, then one chip per user tag (“tag N”). Long-press a tag chip: “Delete tag”.
   • Tap a cover: open that book. Long-press: start multi-select. In multi-select a bar shows the count and buttons: close (X), info (books info dialog), tag (tags popup), heart (add to favorites), empty heart (remove from favorites).
   • The chosen shelf/tag, chip scroll and strip scroll position are remembered.
3. Auto-scroll row (only while auto scroll is armed): play/pause button, speed slider 2-100, speed number.
4. Main icon row:

1. Seek row: current page number, a slider over all pages, total page count. Dragging jumps live and settles on release. Hidden until the book is positioned.
2. Bottom row:

2.5 Tap zones

The screen is divided into a 3 x 3 grid. Each of the 9 zones runs one action. The grid lines can be moved.

Default layout

Default boundaries: left line at 25 % of the width, right line at 75 %, top line at 15 % of the height, bottom line at 85 %.

All assignable actions

Rules

• At least one zone always shows the menu: if you remove “Show / hide menu” from every zone, the middle zone is set back to it.
• While the panels are shown, any tap only hides them (the zone action does not run).
• A tap on a link in the text follows the link instead of running the zone action.
• A tap on a highlight or note opens that annotation instead.
• A tap while text is selected just clears the selection.
• With “Enable tap zones” off, every tap toggles the menu.
• A tap on the chapters bar of the status bar counts as a tap on the zone under it.

The “Tap zones” editor

Opened from the table icon in the top panel. Shows a screen-shaped preview in the current theme colours.

• Tap a zone: a menu of all actions (with icons) to choose from.
• Drag any of the four lines (accent colour, with grips) to resize zones. Limits: an outer zone is at least 5 % of the screen; the middle zone at least 10 %.
• The brightness strip is drawn as a yellow band with a sun; drag its yellow line to change the strip width (2-20 % of the width).
• Menu (three dots): “Enable tap zones” (check), “Brightness strip” (check), “Reset” (default actions and boundaries).

2.6 Gestures in the page

While a selection is being made, page turns are blocked in paged mode so the page does not move under your finger. In scroll mode a mostly vertical motion becomes a scroll instead.

2.7 Keyboard, mouse wheel and volume keys

Keyboard (tablets with a keyboard, Mac running the iPad app)

Keys with Ctrl, Cmd or Alt held are ignored. Keys are ignored while typing in a field and while a selection is being made; otherwise a key press clears the selection and hides the panels.

Mouse wheel / trackpad

• Paged mode: one page turn per wheel gesture. A short pause in the wheel starts a new gesture.
• Scroll mode: the wheel scrolls. Pushing on at the bottom of a chapter opens the next one (and at the top goes back).
• Ctrl + wheel is not taken by the reader.
• “Reverse mouse wheel” flips the direction (default off).

Volume keys (Android only)

• Volume Down = next page, Volume Up = previous page (panels are hidden).
• While auto scroll is armed: Volume Up = speed +1, Volume Down = speed -1 (badge shows the speed).
• While read-aloud is speaking, the keys are left to the system so they change the volume.
• While text is selected, the keys do nothing.
• The system volume panel does not appear when the keys turn pages.
• The switch is not shown on iOS.

2.8 Paged vs scroll, columns, page-turn animation, RTL

Paged and Vertical (scroll) modes

• Switch with the mode label in the footer. The mode is global (applies to every book).
• Scroll mode reads the whole book as one continuous scroll: chapters follow each other automatically.
• In scroll mode, a page turn by tap, key or volume key moves so that the first line not fully visible ends up whole at the top (or, going back, the last such line ends whole at the bottom), instead of a blind full screen.
• In paged mode, the space left under the last whole line is split between top and bottom, so text is vertically centred; the last line of a page is always filled.

Two pages (columns)

Two columns are only offered in paged mode. They split the screen into two equal columns, in portrait too.

Page-turn animation

On: pages slide across quickly and linearly; scroll steps are smooth. Off: instant (better for e-ink).

Reading direction (“Orientation”)

Sets the text direction; page turning flips with it (RTL books turn right-to-left). Note: this is the text direction, not a screen-rotation lock. There is no screen orientation lock in the reader; the screen follows the device rotation.

2.9 Full screen, keep screen on

Full screen: toggle with the top-panel icon or the “Full screen” tap action.

• Android: the system bars hide whenever the panels are hidden; swipe from the edge to show them briefly.
• iOS: the status bar is hidden while the panels are hidden. On an iPhone the area under the camera housing is still kept clear; on an iPad the text goes to the top.

Keep screen on: the screen stays awake for the chosen time after your last touch, page turn or panel change. Steps: 5 minutes up to 60 minutes, then 15 minutes, up to 180 minutes (3 h). “Off” lets the system timeout apply. While auto scroll or RSVP is playing the screen is always kept on.

2.10 Brightness

• Drag up or down inside the strip at the left edge. A badge with a sun shows the level in percent.
• A tap in the strip still runs the tap zone under it; a horizontal swipe still turns the page.
• The strip is not active over a full-screen picture, in RSVP/Accent modes, or while drawing in a PDF.
• Android: changes the brightness for the reader only (the system setting is untouched); it goes back to normal when you leave the book.
• iOS: changes the screen brightness and restores the original value when you leave the book.
• The strip width can also be dragged in the Tap zones editor.

2.11 Status bar and progress display

Choose the mode in Settings -> “Status bar” section -> “Status bar”:

The text area always keeps room for the full bar, so text never runs under it.

Full bar

Two lines:

1. Chapters bar (“Chapters bar”): a rounded progress bar filled to your position, with a thin tick at each chapter start.
2. Facts line (left to right): “Pages left: N” in the current chapter (or the book title when the book has no chapter marks), the clock (HH:MM, 24-hour, updated each minute), a battery icon with the charge in percent (updated every minute), and “page / total”.

When placed at the top, the facts come first and the chapters bar is under them.

• Chapter levels: how many table-of-contents levels get ticks and count for “Pages left”. Counting starts at the first level that has at least two entries.
• Swipe: drag a finger along the chapters bar to move through the book. The position snaps to a nearby chapter tick. A plain tap on the bar is a tap on the page (tap zones).
• If “Back from link” is available, a small back-arrow pill appears at the right end of the bar (long-press clears the history).
• On iPhones with a home indicator, the bar is lowered into the rounded corners and kept clear of them.

Percent mode

Long-press the label to pick it up (haptic feedback, accent border), drag it anywhere, let go. Its place is kept as a share of the screen, so it stays in about the same place after rotation. Double-tap to send it back to the corner.

2.11.1 Configuring the status bar, step by step

1. Open the reader’s Settings (cogwheel in the top panel) and unfold “Status bar”.
2. Tap “Status bar” and pick a mode: “Full · Top”, “Full · Bottom” (default), “Percent” or “None”.
3. With a full bar, turn off what you don’t need: “Chapters bar”, “Pages left in chapter”, “Time”, “Battery”, “Page number”. With the chapters bar off, the facts line stays and the text gets the space back.
4. With “Percent”, the settings change to “Font size” and “Background transparency” of the label.
5. Move the percent label anywhere: close the settings, long-press the “NN%” label until it shows a blue outline, drag it, and let go. It stays there, also after rotating the screen. Double-tap the label to send it back to the bottom-right corner.
6. With “None”, the page shows only the text: no bar, no percent.

What “pages” mean in reflowable books

The page numbers in the seek bar, status bar, Go to page and bookmarks are fixed slices of the book’s text (each chapter counts for at least one). They do not change when you change the font size, margins or screen, so a page number always points to the same place in the book. Fixed-layout EPUBs are counted in their real pages.

The book is marked as read automatically when you reach 99 % or the last page.

2.12 Table of contents (“Contents”)

• Opens from the footer list icon or the “Contents” tap action.
• Nested chapters are indented. Chapters with sub-chapters have a “+”/”-“ button to expand or collapse.
• On opening, everything is collapsed except the branch containing the current chapter, which is highlighted and scrolled into view.
• Menu (shown when the contents have levels): “+ Expand all”, “- Collapse all”.
• Tap an entry to jump there. (Page numbers are shown only for page-based books such as PDF.)
• Empty contents show an empty-state message.

2.13 Go to page and the page previews grid

• Title “Go to page”. A grid of page previews, 3 per row, with the page number under each. The current page is highlighted in blue and the grid opens around it.
• Tap a preview to go there.
• The magnifier icon in the title shows a large number field (hint “1 - N”, digits only, up to 7). Typing highlights that page in the grid; confirm to jump.
• Reflowable books: previews are real renderings of each page with your current theme, font and layout (each preview has the screen’s shape).
• PDF/DjVu/comics: previews are page thumbnails.

2.14 Search in book (“Find”)

• Type the text and confirm (button or keyboard Done).
• Results stream in as they are found; the title shows “Find N…” while searching and “Find N” when done. A “Cancel” link stops the search.
• Each result shows a short excerpt (up to 3 lines) with the match in bold on yellow.
• Tap a result to jump to its exact place.
• Menu: “Clear all” (clears the query and results).
• A new search cancels the previous one. The last query is kept while the book is open.

2.15 Reading themes

Built-in themes

A theme counts as dark when its page colour is dark.

Choosing a theme

• Theme row (top of Settings): one “Aa” swatch per visible theme. Tap to apply. Choosing a light theme also makes it the “Day theme”; choosing a dark one makes it the “Night theme”. The current day and night themes have a short accent underline.
• Moon/Sun button in the footer: switches between the day theme and the night theme.
• “Next theme” tap action: cycles through visible themes.
• “Follow the phone’s day and night mode” (Themes section, default off): the reader switches to the day or night theme whenever the phone’s light/dark mode changes.

Themes section (Settings -> “Themes”)

• One row per theme: drag handle (reorder by dragging), colour swatch, name, and a switch to show/hide the theme in the theme row and in “Next theme” cycling.
• Tap the swatch or name to edit.
• ”+ Add” creates a new theme.

Theme editor (“New theme” / “Edit theme”)

• Live preview card: “Chapter One” and “The quick brown fox jumps over the lazy dog.” in your book font, size and line spacing.
• Contrast ratio in the title, e.g. “12.3:1”; shown in red below 4.5:1.
• “PAGE” colour and “TEXT” colour, each with: a colour code field, ready-made swatches and R/G/B sliders (0-255).
  • Page swatches: 14 ready-made papers, from white through cream and sepia to grey and black.
  • Text swatches: 13 ready-made inks, from black through browns, greens, blues and greys to white.
• “Apply” saves. A new theme is named after its page colour’s hex code. Editing the theme in use applies it at once.
• Menu (existing themes only): “Delete”.

How themes look in the book

• Page and text colours replace the book’s own. When a specific font is chosen (not “Default”) on a dark theme, all text takes the theme text colour, coloured backgrounds in the book disappear and links turn light blue, so nothing disappears on the dark page.
• On dark themes images are dimmed slightly (to 80 % brightness).
• If a book has its own light and dark styles, it follows the reader theme, not the phone setting.

2.16 Paper texture and illustrations

2.16.1 “Paper”

Lays the page on an aged-paper sheet in the theme’s page colour instead of a flat colour: a slightly uneven tone, a warm age tint and fine fibre. Page turns stay fast. On dark themes the warm tint is left out and only the grain shows. The margins are aligned with the page so the whole screen reads as one sheet. Also applies to PDF “Reflow pages”.

2.16.2 “Replace white in images with page color” (multiply illustrations)

On a tinted (not white, not dark) theme, drawings printed on white are blended into the page, so their white background takes the page colour and they look printed on the same paper. Photos and pictures with their own background are left alone. “White level” sets how light a pixel must be to count as the white of the sheet; lower it for books whose scans are greyish. (The Reset button sets it to 90 %.)

2.17 Typography

All of these live at the top of Settings (reflowable books only), except alignment, hyphens and CSS, which are under “Advanced settings”.

Font family

Tap the font name row to open the “Font” picker. Each name is shown in its own font.

Every bundled font comes in Regular, Bold, Italic and Bold Italic.

Picker menu (⋮): “Add fallback fonts”, “Add fonts folder” (see 2.18), “Reader fonts 10” and “My fonts N” (check items to show/hide each group; at least one group stays visible).

How a chosen font is applied (“publisher styles”):

• “Default”: the book keeps its own fonts. Your font size, line spacing, alignment and colours still apply.
• Any other font: the book’s main text gets your font and your size. Everything else keeps its proportion to the main text (headings stay larger, small print smaller, a different face used for, e.g., headings stays). Very wide margins and indents set by the book (4x the text size or more) are halved for phone screens. Drawings and formulas keep their own sizes.

2.17.1 Fallback fonts

A font may not have every letter a book needs: Cyrillic, Greek, accented or rarer characters. Fallback fonts fill those gaps. LibreraX uses your main font first and, for any character it lacks, the next font in the list, in the order you added them.

1. Pick a main font other than “Default” (fallbacks are not offered for “Default”, which keeps the book’s own fonts).
2. In the “Font” picker, tap ”+” in the title, or ⋮ → “Add fallback fonts”. The title changes to “Add fallback fonts”.
3. Tap a font to add it. Add as many as you like; the main font itself is not offered.
4. Back in Settings, the fallbacks are listed under the main font, each in its own face, with × to remove it.

Choosing one of the fallbacks as the main font removes it from the fallback list. Fallback fonts are global, like the main font.

Size, spacing, margins

• Font size can also be stepped by the “Increase font” / “Decrease font” tap actions (by 5); a badge shows it.
• Line spacing applies to running text (paragraphs, lists, tables, captions); headings keep the book’s.
• Tap “Padding” to expand the four sides. The “Padding” stepper sets all four at once; when sides differ, its value is shown greyed. Left/right are a percentage of the screen width; top/bottom are in steps of 4 px.

Alignment

Applies to running text only. Headings keep the book’s alignment, and blocks the book itself centred or set to the far side (titles, epigraphs, verse, captions, signatures) are left as the book placed them. “Auto” leaves the book’s own alignment. Table-of-contents entries are never justified.

Bold text

Thickens all text; each step makes it a little bolder. Shown under Advanced settings, or in the main card when the app uses the E-ink theme (or when it is already on).

Hyphenation

• OFF: no automatic hyphenation (hyphenation points already in the book still work).
• Default: the system’s own hyphenation. It works only for the languages the device provides (on many phones mostly English).
• Hyphen: LibreraX hyphenates the text itself with its own bundled hyphenation patterns. Footnotes shown inline are hyphenated too. Switching to or from this mode reloads the book.

Language chips (next to the “Hyphens” title): the first chip is the book’s own language (as the book states it); tap to turn it on/off. Further chips are languages you added; tap to turn on/off, long-press to select, then the bin icon removes them. The “+” (shown when Hyphens is not OFF) opens a filterable list “ languages" to add one.

• If you named languages, they are used; the book’s language leads only if it is on. Several languages can be on at once: each passage is hyphenated in the language it is marked with.
• A language without a variety (“en”) takes the first available variety (“en-gb”). Serbian uses Serbo-Croatian patterns in Latin or Cyrillic depending on the language code or the text.

Languages available in “Hyphen” mode (76 pattern sets): af, as, be, bg, bn, ca, cop, cu, cy, da, de-1901, de-1996, de-ch-1901, el-monoton, el-polyton, en-gb, en-us, es, et, eu, fi, fi-x-school, fr, fur, ga, gl, grc, gu, hi, hr, hsb, hu, ia, is, it, ka, kmr, kn, la, la-x-classic, la-x-liturgic, lt, ml, mn-cyrl, mn-cyrl-x-lmc, mr, mul-ethi, nb, nl, nn, no, oc, or, pa, pi, pl, pms, pt, rm, ro, ru, sa, sh-cyrl, sh-latn, sk, sl, sq, sv, ta, te, th, tk, tr, uk, zh-latn-pinyin (Czech, Armenian, Indonesian, Latvian, Macedonian and Serbian-own patterns are not included for licensing reasons.)

Languages listed in “Default” mode: on Android, the hyphenation languages the system provides; on iOS this list is empty.

2.18 User fonts

• Settings -> Advanced settings -> “Fonts folder” “+”, or the “+” in the Font picker: choose a folder.
• All .ttf and .otf files in it and its sub-folders are found (hidden files and folders are skipped).
• Files are grouped into families by file name: weight words at the end (Thin 100, ExtraLight/UltraLight 200, Light 300, Regular/Normal/Book/Roman 400, Medium 500, SemiBold/DemiBold 600, Bold 700, ExtraBold/UltraBold 800, Black/Heavy 900, ExtraBlack/UltraBlack 950) and Italic/Oblique/Ital are recognised and removed to get the family name. Example: MyFont-BoldItalic.ttf -> family “MyFont”, weight 700 italic.
• Every weight found can be used by the book; a missing italic or bold is imitated.
• Families appear under “My fonts” in the picker, sorted by name, and take part in “Next font”.
• Fonts named in your user CSS (font-family: "...") are loaded automatically, bundled or user ones.
• On Android the fonts of a folder chosen through the system picker are copied into the app.

2.19 User CSS

Under Advanced settings, row “User CSS”:

• Switch at the right (default on): when on, your CSS is applied to every book and made !important so it wins over the book’s own rules. When off, it is applied only when a specific font is chosen, and without !important.
• ”+” opens “Add”:
  • “CSS file”: load a .css file; its name is shown in a row with an X to remove it. The file’s text is applied before the typed CSS.
  • “Font for text”: pick a font -> adds a p { font-family: "..."; font-weight: normal; font-style: normal; } rule.
  • “Font for headings”: pick a font -> adds an h1, h2, h3, .title { ... font-weight: bold; } rule.
  • “Big first letter”: pick a font (or Default) -> adds a drop-cap rule (::first-letter of the paragraph after h1, h2 or .title, 3em, floated). Each added rule starts with a /* label */ comment.

• FB2 books only: an (i) icon “FB2 tags in CSS” opens a table of FB2 tags and the CSS selectors to use. Tap one to add selector {}. Examples:

  FB2 tag	CSS selector
  epigraph	blockquote.epigraph
  poem	blockquote.poem
  stanza	.stanza
  text-author	.text-author
  empty-line	.empty-line
  notes body	body.notesBodyType
  note links	a[*\|type~="noteref"]

• X: clears the typed CSS.
• Editor: monospace text box (placeholder p { text-align: justify; }), changes apply as you type. The fullscreen icon opens a full-screen “User CSS” editor.
• “CSS error: …“ appears in red under the editor with the first broken part (unbalanced braces, invalid selector, bad declaration).

2.20 Footnotes and links

• Off: a note reference is an ordinary link; tapping it jumps to the note, and “Back from link” returns.
• On: the text of each footnote or endnote (up to 4,000 characters) appears right after its reference, in parentheses, slightly smaller and faded. This works for the note links EPUB and FB2 books mark as notes and for links that lead into a footnote section. Read aloud announces them as “Note N” … “End of note”.
• Back from link: every jump through an internal link is remembered, one after another. Use the footer back arrow, the back pill on the status line, or the “Back from link” tap action to go back step by step. Long-press the arrow to forget the history.
• Web and e-mail links open in the system browser or mail app.

2.21 Text selection and the selection popup

Long-press a word to select it, drag to extend. The selection is a blue tint with round handles, and the handles stay on the right text in two-column pages. The popup appears about 0.5 s after you lift your finger. It is a movable, resizable popup that does not block the page.

Title: “Text” for a new selection, “Notes” for an existing annotation (with its colour dot or bookmark icon).

Rows:

1. The selected text (one line) and a speaker button that speaks just this text.
2. Colour swatches (the chosen colour is remembered):

1. Mark tiles (new selection): Bookmark (adds a text bookmark and a bookmark flag), Highlight, Underline, Strikethrough, Note (opens a “Text bookmark” field: write a note, “Save”/”Cancel”). For an existing note: the Note tile edits its text. Tapping a colour on an existing annotation recolours it. Selections inside an inline footnote cannot be marked.
2. Action tiles: Play (read aloud from the selected paragraph), Delete (existing annotation), Copy (copies and shows “Copy”), Translate (globe, shown when no dictionary/app tiles are shown), then one tile per chosen dictionary or app.
3. Reflowable books: “+ Replace” (opens the Replace dialog with a new rule for the selected text) and “+ Highlight” (a new highlight rule for this text in the chosen colour, applied on every page).

Choosing tiles: the checkbox icon in the title enters edit mode; tap tiles to show/hide them. Menu: “Reset defaults”. By default, installed apps whose names look like dictionaries are shown, plus the web dictionaries Oxford, Cambridge, Longman and Collins.

Translate: Android 10+ uses the system Translate action; otherwise (and on iOS) opens Google Translate on the web with the text.

Built-in web dictionaries (open in the browser)

“From” is the book’s language (2 letters), or “auto” when it is unknown or equals the target; “to” is the app language (or the system language).

Installed apps (Android only)

The popup also offers installed apps: ColorDict-compatible dictionaries (shown in a bottom sheet of 3/4 screen height), “Process text” apps, search apps and share targets. Dictionary and “Process text” apps come first, then the web dictionaries, then search and share apps. iOS shows only the web dictionaries and Translate.

2.22 Highlights, underline, strikethrough, notes, bookmarks

• Annotation types in reflowable books: highlight (tint), underline, strikethrough, bookmark and note (drawn as a small flag). Each stays on the exact text it was made on, even after font or layout changes.
• Tap an annotation in the text: the popup opens with recolour, Delete and, for notes, edit.
• Highlights imported from Librera are placed again by finding their words near their old position.

“Bookmarks” dialog

• Title-bar edit icon: add a page bookmark. Type a name, or leave it empty to use the first words on the page (or “Page N”). Uses the chosen colour filter, else the last annotation colour.
• Colour filter (title bar, shown when more than one colour is used): an “all” ring and one swatch per colour in use.
• Menu: sort by “Recent” (default) or by “Page”.
• Sections: “Bookmarks” (with a bookmark icon in its colour; notes have an edit icon), “Librera” (bookmarks passed in from Librera, if any), “Select” (highlights, underlines, strikethroughs, shown with their style).
• Tap: jump there. Long-press: multi-select; the title shows the count and a bin to delete them.

2.23 Find and replace rules (“Replace”)

Opened from the pen icon in the top panel, the “Replace” tap action, or “+ Replace”/”+ Highlight” in the selection popup. Rules change the displayed text of every book (and what read-aloud says). They are global. There are no rules at first.

Each rule row:

• Mode button, tap to cycle: “=” plain text (accent) -> “.*” regular expression (green, red if invalid) -> off (outlined, rule dimmed). Long-press removes the rule.
• “text” field (what to find) -> arrow -> “replacement” field.
• Highlight rules show a preview of the styled text instead of the replacement field; the chevron opens:
  • line 1: B (bold), I (italic), and text-colour swatches (none + 7 mark colours);
  • line 2: highlight, underline, strikethrough buttons and the mark colour (7 colours). Styles can be combined.

Behaviour:

• Plain rules are case-sensitive; regular-expression rules use JavaScript syntax and support $1-style groups.
• Highlight rules match regardless of case, on every page, without changing the text.
• The replacement may contain simple HTML: b strong i em u s del ins mark small big sub sup span code q, with only a style attribute allowed. Anything else, or unclosed tags, shows “Unsupported or unclosed HTML: …” and the rules are not applied.
• A regular expression that is not valid is skipped.

Toolbar and buttons:

• Edit toggle (circle icon): shows drag handles to reorder and X buttons to remove.
• Menu: “Export” -> saves the rules as LibreraX-replace.txt in the text format @Voice and Librera use (highlight rules are not exported).
• Add pills: “Replace” and “Highlight”.
• Preview (when read-aloud has a current paragraph): “Original” / “Replaced” chips show that text before and after the rules.
• “Apply” saves the rules and reloads the book.

Edition limits: in the FREE edition, only 2 rules can be added, with the note “Free keeps 2 rules. Subscribe to keep as many as a book needs.” Applying rules is a paid feature: in FREE, “Apply” offers a short reward video that unlocks PRO 3H for 3 hours.

2.24 Auto scroll

• Start/stop with the footer play icon or the “Auto scroll” tap action. If the book is paged, it switches to Vertical mode first.
• While armed, a row in the footer has play/pause and the speed slider.
• The page drifts smoothly; the speed is in pixels per second. When it reaches the end of a chapter it waits half a screen more, then continues at the top of the next chapter; at the end of the book it stops.
• A scroll by hand is picked up from where you left it.
• Android volume keys change speed by 1 while armed.
• Works in Accent reading mode as well.
• Keeps the screen on.

2.25 Speed reading (RSVP)

Footer layout icon -> “Speed reading (RSVP)” (in the PRO section of the menu; in the FREE edition the section carries a PRO badge). The mode label shows “RSVP”. Turn it off with the mode label or by choosing “One page”/”Two pages”.

• Shows the text one word (or a few short words) at a time in the centre, on the theme colours, in a serif font.
• One letter of each frame (the recognition point) is shown in the focus colour, and the frame is positioned so this letter stays in the same place. Its position depends on the longest word: 1 letter -> 1st, 2-5 -> 2nd, 6-9 -> 3rd, 10-13 -> 4th, longer -> 5th.
• Words shorter than “Min. letters” are grouped with following words (up to 3 words), never across a sentence or clause end.
• Each frame stays for the time the “Speed” gives one word, longer for frames with several or long words, with pauses after commas, semicolons, colons and dashes, longer ones after a sentence end and the longest at a paragraph end. Words hyphenated across a line break are joined.
• Controls: tap the word to play/pause; the round play button below it; arrows left/right step one frame (when paused). Tap zones “Next page”/”Previous page” jump to the next/previous block of text. Any other tap shows the panels and pauses. The panels hide while playing.
• When paused, the settings card shows (with an (i) “How speed reading works” help dialog):

Focus colours: red, orange, yellow, green, cyan, blue, purple, magenta and blue-grey; the first (crossed-out) swatch turns the focus colour off.

• Reading starts at the top of the current page and moves on through the book; a page with no text shows “No text on this page” and moves on after 1.5 s.
• The paragraph being read is marked in the book behind it, so you return to the right place.
• RSVP mode is remembered: the next reflowable book opens in it. It is not available while a picture is open full screen. Keeps the screen on while playing.

2.26 Accent reading (accent view)

Footer layout icon -> “Accent reading” (PRO section). Mode label “Accent”.

• Shows the text as plain, scrollable paragraphs where the first part of every word is bold and coloured, so the eye catches the start of words.
• Uses your font size, line spacing and alignment, with a serif font, on the theme colours.
• Tap the side zones (“Next page”/”Previous page”) to scroll by 90 % of the screen (animated if animations are on); at the end it moves on to the next part of the book. The middle shows the menu and the settings card.
• Text in this mode can be selected with the system selection.
• Auto scroll works here too.

Every word gets at least one accented letter. Help: (i) “How accent reading works”. Accent mode is remembered. RSVP and Accent exclude each other.

2.27 Relayout pages (PDF only, for reference)

“Reflow pages” is a PDF/DjVu mode (not for comics) that rebuilds each page’s text lines to fit the screen width. It appears in the PDF layout menu and as a switch at the top of Settings, with its own “Font size” stepper (10 % steps, 50-300 %; pinch to change it too). “Add Reflow to mode switch” (Advanced, PDF) adds it to the mode-label cycle. “Reflow to EPUB” (PDF files only) converts the PDF into an EPUB in the Reflow folder (“Page N of M” progress) and opens it in the reflowable reader; such books carry the “[Reflow]” tag. Paper texture and Bold text also apply to reflowed pages.

2.28 The reader Settings dialog, complete layout

Title “Settings”. Scrollable. Changing any setting hides the panels so you see the result on the page.

Top card

1. Theme row (“Aa” swatches).
2. Reflowable books: Font name row; “Font size”; “Line spacing”; “Padding” (expandable: “Top”, “Bottom”, “Left”, “Right”).
3. PDF: “Reflow pages” (+ its “Font size”); “Zoom In/Out” (1.00x-10x, step 0.05).
4. “Bold text” / “Bold amount” here when the app uses the E-ink theme (or Bold text is on).

“Themes” (folding section): theme list, “+ Add”, “Follow the phone’s day and night mode”.

“Status bar” (folding section): “Status bar” mode, then the settings in 2.11.

“Advanced settings” (folding section), reflowable part first:

• “Fonts folder” (+)
• “Text alignment” chips
• “Hyphens” title with language chips and +, then chips “OFF” / “Default” / “Hyphen”
• “Orientation” chips: “Auto” / “LTR” / “RTL”
• “User CSS” (+, FB2 info, clear, switch), CSS file row, editor, error line

then for all books:

“Reset” button (bottom): restores zoom 1x, full screen off, the 6 default themes and the Book theme, font size 120, Literata, line spacing 1.5, padding 5 on all sides, Justify, Auto direction, animations on, volume keys on, TTS page buttons on, Hyphens Default with no extra languages (book language on), user CSS “always” on, images on paper on, inline footnotes off, white level 90 %, full status bar at the bottom with chapter levels 2 and all items on, reverse wheel off, paper off, keep screen on 5 min. (It does not clear user CSS text, replace rules, tap zones or RSVP/Accent settings.)

2.28.1 Window size: double-tap the title

Settings, like every LibreraX window (File info, Contents, Bookmarks, the Font picker and others), opens at its normal size over the page.

• Double-tap the title to make the window fill the screen, so more settings fit without scrolling.
• Double-tap the title again to restore the normal size and place.
• You can also drag a window by its title and resize it from the bottom corners. LibreraX remembers each window’s size and place.

2.29 Global vs per-book

• Global (same for every book, and included in settings backup/sync): all display settings in this chapter: theme and theme list, font, size, spacing, padding, alignment, hyphenation, direction, user CSS, replace rules, paged/scroll, columns, status bar, tap zones, brightness, keep screen on, animations, full screen, RSVP/Accent settings and on/off state, auto-scroll speed.
• Per book: reading position, annotations (highlights, underlines, strikethroughs, notes, bookmark flags), bookmarks, read/unread, favourite, tags.
• The position is saved on every page change; when the book is closed it is saved and a cloud sync is started. On opening, the book goes to the saved place; a book opened from Librera goes to Librera’s place by matching the words at the top of its page.

2.30 Platform differences (Android vs iOS)

2.31 Power-user notes

• No text pinch-zoom in reflowable books: there is no pinch-zoom of the text; use font size. Pinch works only on a full-screen picture (and in PDFs).
• Footer back arrow and status back pill both use the same link history.
• Settings popups remember size and position per dialog (drag/resize them).
• Seeking is queued: dragging the seek bar or chapters bar fast only performs the last requested jump, so you never land on an intermediate chapter.
• A saved position that no longer fits (book changed) falls back to the start of the text instead of failing.
• Librera hand-off (Android): when Librera opens a book in LibreraX, it can pass the view mode (scroll/paged), full screen, its place, bookmarks and annotations; these are imported.
• Go to page previews never disturb the page you are reading.
• Book fonts: whether the book’s own fonts are replaced follows the chosen font (“Default” = book’s fonts).

Part 3 — Formats, PDF and comics, notes and bookmarks

Section A lists every supported format, what LibreraX shows about it and what it can save back. Section B covers the page reader for PDF, DjVu, CBZ and CBR: zoom, fitting, cropping, layouts, recolouring, reflow, drawing and annotations. Section C covers bookmarks, highlights and notes, and how they sync.

3.A Formats

3.A.1 Master list of extensions

A library scan picks up exactly these extensions:

pdf, epub, mobi, azw, azw3, kf8, prc, fb2, fb2.zip, cbz, cbr, txt, md, html, xhtml, doc, docx, rtf, zip, djvu, djv

Good to know:

• A name ending in .fb2.zip is always treated as an FB2 book, never as a plain .zip.
• .markdown files open when you open them directly, but a library scan does not pick them up.
• Upper and lower case in extensions do not matter.

3.A.2 Formats at a glance

A zip counts as a book only when it holds exactly one book of a supported format.

3.A.3 Which reader opens which file

• Reflowable reader — foliate-js inside the system WebView: EPUB, MOBI/AZW/AZW3/KF8/PRC, FB2/FB2.ZIP, TXT, MD, HTML/XHTML, DOC, DOCX, RTF. The last six are turned into one web page first, so all reflowable-reader features apply.
• Page reader: PDF (PDFium on Android, PDFKit on iOS), DjVu (Android, drawn by Librera PRO), CBZ and CBR.
• A .zip is unpacked first and opened by the reader for the book inside.

3.A.4 Format details and limits

EPUB

• Damaged books with small markup errors are repaired where possible and still open.
• All authors are shown, joined with “, “.
• Series come from Calibre series data or from EPUB 3 collections.
• A year of 101 or lower is shown as undefined.
• The page count is an estimate based on the size of the text.

MOBI / AZW / AZW3 / KF8 / PRC

• No series is shown for these formats.
• The page count is an estimate based on the length of the text.

FB2 / FB2.ZIP

• In a .fb2.zip, the first .fb2 file inside is read.
• The annotation is shown as one paragraph.
• Only the first series of the book is shown.
• The page count is an estimate based on the size of the text.

TXT / MD / HTML / XHTML

• The text encoding is detected automatically, including UTF-8, UTF-16 and the older code pages windows-1251, windows-1252, KOI8-R and ISO-8859-1.
• TXT: paragraphs are split at blank lines; single line breaks are kept.
• Markdown: GitHub-flavoured (tables, strikethrough and so on).
• Converted text gets a simple page style: tables with borders, wrapped code blocks, pictures no wider than the page, a line to the left of quotations, thin rules.
• HTML: only the language is read. The page title is ignored on purpose (a saved web page names the site, not the book), so the title stays the file name.
• The page count is an estimate based on the file size.

DOC / DOCX / RTF (office formats)

• LibreraX looks at the content, not only the extension, so a .doc that is really a web page or plain text still opens.
• The document is shown as one reflowable page.
• Kept: paragraphs, headings (Word heading styles; the “Title” style becomes the top heading), bold, italic, underline, strikethrough, superscript and subscript, line breaks, bulleted and numbered lists (also nested), tables (also nested), links (to web addresses and to places in the document), footnotes and endnotes (collected after the text, with links back), and pictures. Hidden text is left out; tabs become a space.
• Pictures: PNG, JPEG, GIF, BMP and WEBP. In RTF only PNG and JPEG pictures are shown; other picture types are skipped.
• RTF documents in Western, Cyrillic, Greek, Turkish, Japanese, Korean and Chinese code pages are shown correctly.
• RTF metadata is read from the first 1 MB of the file only.
• The page count is an estimate based on the file size.
• A title or author with no letter or digit in it is ignored.

PDF

• Password-protected PDFs: a dialog asks for the password — “This file is protected. Enter the password to open it.”; on a wrong one — “Wrong password. Try again.”. Cancelling closes the book.
• The text layer gives selection, copy, read aloud, search and the links on the page.
• On iOS, text printed twice on top of itself is read aloud only once.
• Android: very large JPEG 2000 pictures on a page may be left out so that the page can open without running out of memory.
• Table of contents: the PDF outline, with its levels, on both platforms.
• Search ignores upper and lower case and finds at most 500 hits in total and 20 per page; each hit shows about 40 characters before and about 60 after.
• Metadata: see 3.A.2 and 3.A.5.

DjVu (Android only, through Librera PRO)

• LibreraX draws DjVu pages through the separately installed app Librera PRO.
• Required version: “Librera PRO %1$s or newer is required.” with %1$s = 9.6.
• Messages:
  • not installed: “To support DJVU, please install Librera PRO. DjVu pages are drawn by Librera PRO’s DjVu engine.” with the button “Install Librera PRO”;
  • installed but too old: “To support DJVU, please update Librera PRO. The installed version cannot draw DjVu pages for LibreraX yet.” with the button “Update Librera PRO”;
  • no answer within about 10 seconds: “Librera PRO is not answering. Open it once, then try again.” The buttons open Google Play.
• DjVu supports: page display with crop, text (selection, copy, read aloud, search), table of contents, Half page, Bold text, Reflow pages, RSVP and Accent modes. DjVu does not support saving annotations into the file (they stay in LibreraX).
• In Library settings → “Formats” the switch “DJVU” shows the note “with Librera PRO” (or “Update Librera PRO”); turning it on without Librera PRO opens an info sheet instead. DjVu files are not listed when Librera PRO is not installed.
• On iOS the DJVU switch is hidden and DjVu files are not shown.

CBZ / CBR (comics)

• LibreraX looks at the content, not the extension, so a .cbz that is really a RAR archive (or the reverse) still opens.
• Pages: every .jpg .jpeg .png .webp .gif .bmp image whose name does not start with “.”; in plain alphabetical order of the full path inside the archive, ignoring case (“page10” comes before “page2” unless the numbers have leading zeros).
• RAR 4 and RAR 5 archives are supported; a single image larger than 512 MB is refused. Jumping backwards in a very large RAR archive can be slow.
• Comics have no text: no selection, search, read aloud, Reflow pages, RSVP, Bold text and no table of contents.

ZIP

• A ZIP is a book only when it holds exactly one book of a supported format; with two or more books it is not a book.
• The book inside opens in its own reader.
• Annotations cannot be saved into a PDF that is inside a ZIP.

3.A.5 Platform differences (formats)

3.A.6 Metadata writing (“Edit metadata”)

• Available from the book’s “File info” dialog → “Edit metadata”, only when the file can be written and is .epub, .fb2, .fb2.zip or .pdf. The dialog notes: “Saving writes these fields into the book file itself.”
• Fields: “Book Cover” (EPUB/FB2 only), “Title”, “Author” (list), “Series”, “# in Series”, “Genre” (list), “Language”, “Publisher”, “Publication Date”, “ISBN”, “Annotation”.
• Cover choices (EPUB/FB2): pick an image file, or “From the book” — any image already inside the book.
• Safety: LibreraX writes a new copy, checks it, and only then replaces the original. Books from cloud or other storage locations are written back to where they came from.
• After saving, the cover and metadata are refreshed in the library.

EPUB:

• The series is saved so that both Calibre and EPUB 3 readers recognise it.
• The ISBN is saved as the book’s identifier, and the book’s modification date is updated.
• A new cover is added to the book as a new image and marked as the cover.

FB2:

• The file keeps its own text encoding; a .fb2.zip stays zipped.
• Authors are saved split into first, middle and last name.
• Formatting in the annotation (headings, bold, italic) is kept.
• Other book information in the file (keywords, translators and so on) is kept.
• A new cover is added to the book and set as the cover page.

PDF:

• The original content of the file is kept unchanged; the new information is added to it.
• Title, author, annotation and genres are saved in the standard PDF fields that other apps show. Publisher, series, number in series, ISBN and language are saved too, but only LibreraX shows them.
• Encrypted PDFs cannot be edited.
• The cover of a PDF cannot be changed.

3.A.7 Comic metadata (ComicInfo.xml + file name)

If the archive contains a ComicInfo.xml, LibreraX shows its series, number, volume, issue count, title, date, writer (or penciller, as author), publisher, genre, language, summary (as annotation) and tags (as keywords).

The title is shown as Series Vol. N #Number (of Count) - Story (“Vol.” only for volumes below 1000).

The file name fills in whatever ComicInfo.xml does not give:

• In brackets ( ) [ ] { }: a year 1900–2040, YYYY-MM(-DD), Mon YYYY, of N (issue count), and the tags digital → “Digital”, webrip → “Webrip”, c2c, noads → “No ads”, adult → “Adult” (shown as keywords).
• Web-site names (*.com/.net/.org/.ru/.to/.me/.cc/.info) and underscores are removed.
• Volume words: v, vol, vol., volume, том, т.; chapter words: c, ch, ch., chapter, глава, гл.; issue: #12, 12 of 50, or a number at the end (up to 4 digits; a number 1900–2040 is taken as the year).
• Leading zeros of issue numbers are dropped (007 → 7).

3.A.8 Office file-name metadata

For DOC/DOCX/RTF the file name overrides the title and author inside the file when it looks like Author - Title - Year:

• separators: ` - , – , — ; a leading running number (12_, 3., 1-2) and trailing "copy" markers (- copy, - копия, - kopie, - kopia, - copie, (2)`) are removed;
• a year 1500–2099 at the end (with or without brackets) becomes the year;
• if the last part matches the author named inside the file, the order Title - Author is recognised;
• Surname, Given becomes Given Surname; several authors can be joined by & or ;;
• when both names share a surname, the fuller author name from the file is used.

3.A.9 Calibre metadata.opf

With Settings → “Other settings” → “Calibre metadata.opf” on (default off), a metadata.opf in the book’s folder is read and its filled-in fields take priority over the book’s own metadata (the number in series comes together with the series).

3.A.10 Library “Formats” switches

Library settings → “Formats”, two columns of switches (all on by default; ZIP is always on):

• Column 1: “PDF”, “EPUB”, “MOBI/AZW” (mobi, azw, azw3, kf8, prc), “DOC/DOCX/RTF”
• Column 2: “FB2” (fb2, fb2.zip), “TXT/MD/HTML” (txt, md, html, xhtml), “CBZ/CBR”, “DJVU” (Android only, needs Librera PRO)
• The last group that is still on cannot be switched off.

3.B PDF and page-image reader (PDF, DjVu, CBZ, CBR)

3.B.1 Capability matrix by format

3.B.2 Reading modes and the mode button

• The mode button in the bottom panel switches the scroll mode and shows the current mode name: “Paged”, “Vertical”, “Reflow”, “RSVP”, “Accent”.
• “Paged” = pages turn sideways, one screen (one page, a spread, or a half) per swipe. The page turn is animated when “Enable animations” is on.
• “Vertical” = one continuous vertical strip of pages, each fitted to the screen width.
• Setting “Add Reflow to mode switch” (Advanced settings, default off): when on, the mode button cycles Paged → Reflow → Vertical → Paged; when off it toggles Paged ↔ Vertical.
• The default is “Paged”; the choice applies to all books.

3.B.3 Page layout menu (bottom panel layout icon)

Items (icons change with the current layout):

• “Half page” — splits each page into its left and right halves shown one after another (PDF and DjVu only). The order of the halves follows the reading direction: RTL shows the right half first. The reading direction is the “Auto / LTR / RTL” choice in the reflowable reader’s text settings (default Auto). Default off.
• “One page” (default).
• “Two pages” — two pages side by side at the same height, fitted and zoomed as one sheet; the last page of an odd book stays on the left beside a blank. Not offered in Vertical mode. Spreads are always ordered left to right (no manga order). Default off.
• A PRO section (badge shown in the FREE edition) with: “Reflow pages”, “Speed reading (RSVP)”, “Accent reading” (not for comics) and “Reflow to EPUB” (PDF only).
• Choosing a layout turns off Reflow / RSVP / Accent; changing the layout resets zoom to 1×.

3.B.4 Zoom and fitting

• Fitting: Paged with one page → the whole page fits the screen; Two pages → both pages fit at equal height; Vertical → page width = screen width.
• Pinch to zoom: Paged 1×–10×, Vertical 1×–8×; you cannot zoom out below fit (1×). Drag with one finger to move around a zoomed page.
• Settings stepper “Zoom In/Out”: shows e.g. “1.25x”, step 0.05, range 1×–10× (hidden while Reflow pages is on).
• Double tap while zoomed → back to fit (1×). At fit, taps go straight to the tap zones without delay.
• The zoom level (default 1×) is remembered for all books and kept when you reopen a book.
• Changing One/Two pages, or “Reset” in reader settings, sets zoom back to 1×.
• During a pinch the page may look blurred for a moment; it becomes sharp when you lift your fingers.

3.B.5 Crop margins

Opened from: the crop icon in the top panel (highlighted when crop is on), Reader settings → “Advanced settings” → “Crop margins” switch, or a tap zone set to the action “Crop margins”.

Dialog “Crop margins”:

• Chips: “Off”, “Auto”, “Manual”.
• “White level” stepper (Auto only): 50–100 %, step 5; default 85 % (“Reset” of reader settings sets 90 %). Lower = more aggressive cropping.
• Large page preview with four draggable lines (left, right, top, bottom). At least 20 % of the page must stay in each direction. Areas outside are shaded; the printed area found by Auto is outlined in green.
• Arrows “<” and “>” step through pages to check the crop on other pages.
• Menu: “Reset” (area back to the full page). Button: “Apply”.

Behaviour:

• Auto: finds the printed area of each page (also on coloured or gradient paper), leaves a small margin, and does not crop a page where it finds too little print. The manual lines are the outer limit for Auto.
• Manual: the same area is cropped on every page.
• Normal pages and Half page mode have separate manual areas.
• Crop applies to all page readers (PDF, DjVu, comics) and to all books, not per book. Crop is off by default; when you turn it on, “Auto” is selected.
• Reflow pages uses the cropped area.

3.B.6 Gap between pages

• “Gap between pages” (Advanced settings), default on: 4 dp between pages in Vertical mode (no gap when off).

3.B.7 Colours: themes, night recolouring, Paper, Bold text

• Pages follow the background colour of the reader theme.
• Light themes with a non-white background: white paper takes the theme colour, black text stays black.
• Dark themes: the page is inverted — white becomes the theme background, black becomes white (pictures are inverted too).
• The sun/moon icon in the bottom panel switches between the system day and night theme.
• “Paper” (Advanced settings, default off): a paper texture is shown under the page.
• “Bold text” switch (default off) + “Bold amount” stepper 1–5, default 2: makes the letters thicker; each step adds more. Offered for PDF and DjVu (not comics).

3.B.8 Page previews (“Go to page”)

• Opened from the page icon in the bottom panel or a tap zone “Go to page”.
• A grid of 3 columns of page thumbnails (in the current night/theme colours), page number under each; the current page is highlighted. Tap a thumbnail to go there.
• The search icon in the title opens a number field with hint “1 - N” (up to 7 digits); Enter jumps.
• The bottom panel also has a page slider with the current page and total.

3.B.9 Text selection (PDF, DjVu)

• “Text selection” must be on (default on, toggled by the tap action “Text selection”: “Text selection on” / “Text selection off”).
• Long press without moving selects the word; drag to extend. Two round handles at the ends can be dragged afterwards. A selection stays within one page.
• After a short moment the selection toolbar appears (see 3.C.4). In Draw mode with a text style active, the selection is marked at once instead.

3.B.10 Reflow pages (in-reader text reflow)

• Label “Reflow pages”; toggle in Reader settings or the layout menu; mode name “Reflow”. Not for comics. PRO badge in FREE.
• Works from the page image, not the text layer: words are re-arranged into lines that fit the screen width. So it also works on scanned PDFs and on DjVu without text.
• Recognises columns, centred lines, headings, paragraph gaps, words hyphenated at line ends (joined again), tables and figures (kept as pictures) and dotted leaders.
• Pages that are mostly pictures, or have very few lines of text, are shown as the whole page.
• Continuous vertical scrolling; tapping the sides scrolls by 90 % of the screen.
• “Font size” stepper (shown only while reflow is on): 50 %–300 %, step 10 %, default 100 % (body text about 19 dp). Pinch also changes it.
• Uses the current crop, night/theme colours and Bold text.
• Highlights, notes, selection and the read-aloud marks are shown on the reflowed words.
• Drawing is not available while Reflow, RSVP or Accent is on.
• Reflow pages is off by default.

3.B.11 Reflow to EPUB (PDF only)

• Menu item “Reflow to EPUB” (layout menu, PRO section). Dialog note: “Text, pictures and headings of this PDF become a reflowable EPUB in the Reflow folder.” Progress: “Page %1$d of %2$d” with a bar; failure: “This PDF could not be reflowed.”; button “Cancel”.
• Result: <book name>.epub in the app’s Reflow folder; if it already exists it opens at once without being rebuilt. The new EPUB opens automatically when done.
• What you get: the PDF’s text (bold and italic kept), headings by font size, pictures cut out of the pages, repeated headers, footers and page numbers removed, words hyphenated at line ends joined, links kept, chapters and a table of contents from the PDF outline, and a cover from page 1.
• Title and author come from the library entry; the language comes from the library.
• The password already entered for the PDF is used.

3.B.12 Annotations on PDF / DjVu / comics — overview

Kinds of annotations:

3.B.13 Draw mode and the Draw bar

Opened with the pen icon in the bottom panel (page reader, only when Reflow/RSVP/Accent are off). The Draw bar sits above the bottom panel; on narrow screens (below 740 dp) it uses two rows.

Draw bar contents, left to right:

1. Line width button — opens a list of widths.
   • Ink widths: 1.5, 3, 5, 8, 12 dp (default 3).
   • When Underline or Strikethrough is the active style, the list shows mark line widths 1, 1.5, 2.5, 4, 6 dp (default 2.5).
2. Text styles: Highlight, Underline, Strikethrough. Tap one, then select text → the style is applied in the current colour. Tapping the active style again turns it off and returns to ink.
3. Shapes — four groups; each group shows its last used shape; tap again (or long press) on a group with a small corner triangle to pick another shape:
   • Free hand
   • Line, Arrow, Double arrow
   • Rectangle, Rounded rectangle, Ellipse (circle fitted to the dragged box)
   • Star, Heart The last shape of each group is remembered.
4. Delete (bin) — shown when an annotation is picked; deletes it.
5. “PRO” badge (FREE edition only; opens the PRO offer).
6. Colours — 7 swatches: yellow, green, blue, pink, orange, red, black. Default ink colour red. The colour you choose also becomes the default annotation colour. Tapping the current colour again pauses inking (so the page can be scrolled).
7. Done (check mark) — shown when an annotation is picked; releases it.

Drawing behaviour:

• One finger draws; a second finger cancels the stroke (so pinch and scroll still work).
• Shapes are previewed live and replaced by the final outline when you lift your finger.
• Line width grows and shrinks with zoom.
• Picking: tap an ink stroke, a text mark, or an annotation already in the PDF file to pick it (dashed accent frame). While picked:
  • colour swatch → recolour; width → change width (ink and file annotations);
  • drag inside the frame → move (ink and movable file annotations);
  • drag a corner dot (ink only) → resize; rectangles stretch freely, other shapes keep their proportions; minimum 12 dp;
  • text-style tile on a picked highlight/underline/strike → change its type;
  • bin → delete; check → release.
• To delete a mark, pick it and tap the bin.

3.B.14 Saving annotations into the PDF file

• Switch “Ask to save annotations into the PDF file” (Advanced settings, PDF only), default off.
• When on and you close a book with annotations that can be saved, the dialog “Save annotations into the PDF file?” offers “Save” / “Don’t save”. On failure: “Could not save annotations into the PDF file”.
• Can be saved: ink drawings, and highlights / underlines / strikethroughs placed on the page. Cannot be saved: bookmarks, notes, page bookmarks, and highlights imported from Librera that have not been placed on the page yet.
• They are saved as standard PDF annotations (ink, highlight, underline, strikeout, with the selected text) in the chosen colour and line width, so other PDF apps show them. The file is checked before it replaces the original, and books from cloud or other storage locations are written back to where they came from. After a successful save the marks live in the file and no longer as separate marks in LibreraX.
• When a changed book belongs to Google Drive, it is uploaded again on close.
• Not possible for PDFs inside a ZIP, for DjVu or for comics. iOS cannot save into encrypted PDFs; Android uses the PDF password.

3.B.15 Editing annotations already inside a PDF (“PDF editing”)

• Annotations already in the file can be picked in the reader (tap when drawing is possible).
• Recognised types (both platforms): Text (sticky note), FreeText, Line, Square, Circle, Polygon, PolyLine, Highlight, Underline, Squiggly, StrikeOut, Stamp, Caret, Ink. Hidden annotations are ignored.
• Move: all except the text markups (Highlight, Underline, Squiggly, StrikeOut).
• Recolour / change width: Text, Square, Circle, Highlight, Underline, Squiggly, StrikeOut, Ink.
• Delete: any recognised type.
• Each edit is saved into the PDF at once (also written back to cloud or other storage locations). On failure: “Could not save annotations into the PDF file”.

3.B.16 Comic reading options

• Comics use the same page reader: Paged / Vertical, One page / Two pages, zoom, crop (Auto crop works on scans too), themes/night recolouring, Paper, page preview grid, ink drawing (kept in LibreraX, never written into the archive).
• Not available for comics: Half page, Reflow pages, RSVP, Accent, Bold text, text selection, search, TTS, table of contents, saving annotations into the file.
• Page order is the alphabetical order of the images in the archive (3.A.4). There is no right-to-left/manga page order and no RTL spread option; Two pages always places the lower page on the left.

3.B.17 Other page-reader details

• Opening position: the saved page; if the number of pages changed since (e.g. the file was replaced), the position is moved proportionally.
• Bookmarks and annotations jump to their saved page.
• Text-to-speech on PDF/DjVu reads sentence by sentence and highlights the sentence being read on the page.
• The tap zone action list includes “Crop margins” (PDF reader only; other readers ignore it) and “Text selection”.
• Top panel (page reader): fullscreen, book info, crop (instead of the text reader’s edit/pen icon), tap zones, settings. Bottom panel: library, pen (Draw), search, go to page, bookmarks, contents, day/night, page layout, back.

3.C Notes and bookmarks

3.C.1 What kinds of marks exist

Bookmark vs text bookmark: a plain bookmark remembers a position (page or place in the book and the words there); a text bookmark is tied to the exact selected text and is drawn as a flag next to it.

3.C.2 Colours

• The same 7 swatches everywhere: yellow, green, blue, pink, orange, red, black.
• Default annotation colour yellow; the last colour picked in the selection toolbar or Draw bar becomes the new default.
• A new page bookmark takes the colour filter currently selected in the Bookmarks dialog, else the default colour.

3.C.3 How marks are drawn

• Reflowable reader (EPUB etc.): annotations are drawn in the text by type and colour (page bookmarks and imported marks that have not been placed in the text yet are not drawn).
• Page reader: highlight = semi-transparent colour box; underline/strike = solid line (in the mark line width); bookmark/note = coloured flag left of the first line; ink = stroke; the picked annotation gets an extra tint.
• In lists: highlights show the text on a light colour background; underline/strike show the text in the mark colour with underline / line-through.

3.C.4 Selection toolbar (both readers)

• Title “Text” for a new selection, “Notes” when an existing annotation was tapped; a colour dot (or the bookmark flag) leads the title. The header shows the selected text and a speaker button (speak it).
• Row of the 7 colour swatches (tapping recolours a selected annotation).
• Tiles for a new selection: Bookmark, Highlight, Underline, Strikethrough, Note (pencil).
• Tapping an existing note: pencil to edit its text (the matching bookmark is renamed too).
• Tapping an existing PDF highlight/underline/strike: three type tiles to change its type.
• Second row: Play (start TTS from the selection), Delete (bin, for an existing annotation), Copy, Translate (globe) when no apps are chosen, then your chosen dictionary/translator apps; an edit toggle chooses which apps are shown; menu “Reset defaults”.
• Reflowable reader only: wide buttons “+ Replace” and “+ Highlight” create a text-replacement rule (the Highlight rule highlights every occurrence of the text in the chosen colour).

3.C.5 Bookmarks dialog inside the reader

• Title “Bookmarks”; opened from the bookmark icon in the bottom panel or the tap action “Bookmarks”.
• Title bar: pencil icon = add a page bookmark (field “Text bookmark”, empty allowed; an empty name becomes the words at the current place, or “Page N”).
• Colour filter: when marks use more than one colour, a ring “all” plus one swatch per colour used; tapping a swatch shows only that colour (an underline marks the active swatch). The filter hides Librera bookmarks.
• Menu (sort): “Recent” (newest first) or “Page” (book order). Shared with the Bookmarks screen, default Recent.
• Sections:
  1. “Bookmarks” — bookmarks, text bookmarks and notes (flag icon in their colour; notes have an edit button; inline rename).
  2. “Librera” — imported Librera bookmarks (if any; jump only).
  3. “Select” — highlights / underlines / strikethroughs (and any other text mark not already listed above). Empty sections show “-“.
• Tap a row → jump to that place.
• Long press → multi-select (count in the title) → bin deletes; deleting a bookmark also deletes its flag or note.

3.C.6 Bookmarks (Notes) screen — main app tab

Layout:

• A tab in the home screen labelled “Notes” (bookmark icon). Empty state: “Notes”; with a search that finds nothing: “Nothing here”.
• One page per book that has at least one bookmark or text mark, the book with the newest mark first (the book appears once, even when several copies of it exist). Swipe left/right between books.
• A strip of chips under the top bar: one chip per book (title, max 160 dp), the current one highlighted; while searching, a counter on each chip shows how many matches that book has. Tapping a chip jumps to that book.
• Book card at the top: compact book row (cover, title, author, etc.) — tap opens the book, long press selects the book; a “READ” badge/button when reading has started (opens the book); the book’s tags as chips (tap → tags editor). Scrolling up folds the card into a small cover + title in the top bar (tap the cover to unfold, the title to open the book); the “Read” check and “READ” button then appear in the bar.

Top bar actions:

• Search (magnifier): opens a find row; filters across all books by bookmark and annotation text (upper and lower case ignored); books without matches are hidden; closing the search clears it.
• Menu (⋮): “Recent” / “Page” sort (same setting as the reader dialog, default Recent).
• With marks selected: count shown, close (X), bin deletes all selected marks.
• With the book card selected (long press): the standard book actions — info (“File info”), tags, favourite star on/off, send/share the file, delete the book, add to / remove from the library, mark read / unread, reload metadata, upload to Google Drive (if not in the cloud yet), open with another app.

Per-book list:

• Section “BOOKMARKS”: bookmarks, text bookmarks and notes. Each row: bookmark icon in the mark’s colour (default colour when it has no flag), the text (2 lines max), and for notes an edit (pencil) button → inline “Text bookmark” field (“Cancel” / “Save”; renaming updates both the bookmark and the note).
• Section “SELECT”: highlights / underlines / strikethroughs (3 lines max), styled as in 3.C.3. Ink drawings are never listed.
• Empty sections show “-“.
• Sort: “Recent” = newest first; “Page” = in book order.
• Tap a row → opens the book at that place.
• Long press → multi-select (accent background); the bar shows a bin to delete them.
• Each row shows only the text (with its colour and style). Dates and page numbers are not shown.

Export / share:

• There is no separate export or share of bookmarks and notes. They are included in the app backup (Settings → backup “Export”) and in cloud sync.

3.C.7 Sync

• Bookmarks, notes, highlights and drawings are kept in LibreraX on the device (not in the book file, unless you save them into a PDF, see 3.B.14) and sync with your other devices. They follow a book that was moved, renamed or opened from another copy.
• Syncing uses the cloud account, together with the other book data (“Sync bookmarks, notes, reading progress and settings across all your devices through the cloud.”).
• The same file on any device gets its marks. When the same mark was changed on two devices, the latest change wins; deletions sync too.
• Marks for a book that is not on this device wait and appear when the book does.
• The cloud info screen counts “Highlights”. Deleting the cloud data removes “reading positions, bookmarks, notes, favourites, tags and read marks” from the cloud only.
• Librera import brings “%1$d bookmarks” and “%1$d highlights” (matched by file name).

Part 4 — Reading aloud, widgets, watches, cars and integrations

Text to speech and everything that controls it from outside the app: the notification and lock screen, headset buttons, home-screen widgets, Wear OS and Apple Watch, Android Auto and CarPlay, automation, opening books from other apps, the Librera integration and e-ink devices.

4.1 Overview

4.2 Where Read Aloud lives in the app

Ways to start or control reading aloud:

“Turn pages with volume keys” (Reader settings) is ignored while the voice is speaking, so the volume keys change the volume during read-aloud.

4.2.1 Background reading (leaving the book while it is being read)

• If you close a book while it is being read aloud (or is paused in read-aloud), the book keeps reading in the background. Playing stays playing, paused stays paused.
• The Library’s top bar then shows a headphones icon instead of the app logo, plus a play/pause button. The covers shown next to it (the “reading now” strip) open the book when tapped.
• Tapping the headphones icon hides this read-aloud header (it comes back the next time reading starts or pauses in the background).
• If you press play in the header when no book is loaded, the first “reading now” book starts reading in the background.
• Opening the same book again picks up seamlessly (the voice keeps going).
• Background reading ends once reading is stopped (not merely paused). If reading has not started within 30 seconds, it gives up.
• iOS: background reading also works from the home screen while no book is open.
• Android: the TTS widget’s play button, when nothing is loaded, starts reading the last book in the background without showing the reader (§4.7.3).

4.3 The “TTS” dialog

Title: “TTS”. On Android 13 and later, the first time you open it, it asks for permission to show notifications (needed for the playback notification). The question is asked only once.

Title-bar action: cogwheel icon → opens the system text-to-speech settings (same as “TTS settings”).

4.3.1 Overflow menu

4.3.2 First card: voice

Rows have left-aligned uppercase labels.

Below the rows: the big transport — previous / play-pause (larger, filled) / next. Previous/next move one paragraph (sentence in PDF) within the current page (see §4.4.4).

4.3.3 Voice picker

• Searchable list (filter field); the last search is remembered.
• Each entry: language (title), voice name + “Not downloaded” flag (subtitle). The selected voice is marked.
• Overflow menu with two filters; only one can be on at a time, tap again to clear. The choice is remembered (default: all voices):
  • “Only local voices” — voices that do not need a network connection.
  • “Only network voices” — voices that need a network connection.
• iOS reports every voice as local, so “Only network voices” shows an empty list on iOS.

How Android voices are named:

• The language title is the language name; when the engine has the same language for several countries it includes the country (e.g. “English (United Kingdom)”).
• Network voices that are not installed are hidden.
• Order: voices of the language currently being spoken first, then installed before not downloaded.
• When you install, update or remove a speech engine app, the engine list refreshes by itself and the engine restarts if needed.

iOS voices: the title is “ ()", e.g. "English (en-US)"; the subtitle is Apple's voice name. Voices of the device's language come first, enhanced/premium quality before default quality. If no voice was chosen, the first voice of the device language is used.

4.3.4 Second card: reading behaviour

Highlight swatches: Yellow · Green · Blue · Pink · Orange · Red · Black. Picking one closes the row and recolours the current highlight at once.

4.3.5 Sleep timer behaviour

• Not remembered: after the app restarts it is “Off” again.
• The countdown starts when reading is playing (or when chosen while playing).
• It counts real time: it keeps running while paused.
• When it reaches zero, reading pauses (it is not stopped, so you can resume) and the timer returns to “Off”.
• Stopping read-aloud (“Close” in the notification, end of book, etc.) cancels the countdown; the chosen duration is kept and the next Play starts it again from the full time.
• Choosing “Off” cancels it.

4.3.6 Replacement rules (“Replace” editor)

The TTS editor is titled “Replace”. It changes what is spoken, not what is shown. (The book’s own display “Replace” uses the same editor but without files.)

Each rule row:

File rows (rule files, see below): a check-mark square (tap = enable/disable, long-press = remove), a file icon, the file name and a status line: “N rules”, “…” while loading, a spinner while reading, or “The file could not be read” in red.

Title-bar edit toggle (circle-remove icon): turns on edit mode, which shows

• a drag handle (≡) on each row for reordering by dragging,
• a delete (×) button on each row,
• a pen button on readable file rows → opens that file’s own rules in a nested editor (§4.3.6.2).

Bottom buttons:

• “Add” — new empty rule.
• “Add file” — pick any file (system file picker) to use as a rules file. LibreraX keeps access to it.

Live preview (shown when something is currently being read): a divider, two chips “Original” / “Replaced” (default “Replaced”), and the current paragraph shown with the rules as you edit them; a small spinner shows while it updates.

Overflow menu: “Export” — saves the current rules as a plain-text rules file named LibreraX-tts-replace.txt through the system save dialog; a short “Export” message confirms.

Main button: “Apply” (with a reward tag in the free edition).

Free vs PRO:

• The free edition keeps at most 2 rules. With 2 or more rows the add buttons are replaced by: “Free keeps 2 rules. Subscribe to keep as many as a book needs.”
• In the free edition “Apply” offers a rewarded video; watching it unlocks PRO for 3 hours and then applies the rules. Paid users apply directly.
• The nested file editor has no limit and no video.

How rules are applied:

• Top to bottom; each rule works on the result of the previous one.
• A file row applies all enabled rules of that file at its place in the list.
• Plain rules: exact text, case-sensitive, every occurrence is replaced.
• Regular-expression rules: every match is replaced; the replacement can use group references such as $1.
• Disabled rules and rules with an empty “text” field are skipped. Empty rules are removed on “Apply”.
• Removing a file row ends LibreraX’s access to that file.
• Rule files are read again every time a book is opened.

4.3.6.1 Special control words in replacements

Type these words into a replacement. When the spoken text of a paragraph contains them:

Pieces with no letters or digits are not spoken; a paragraph with nothing speakable becomes a short silence.

4.3.6.2 Rules file format (import / export / edit in place)

Plain UTF-8 text, one rule per line:

"find" "replace"          plain rule
"*pattern" "replace"      regular expression ( a leading * before the opening quote also works: *"pattern" "replace" )
"#find" "replace"         disabled rule (#* = disabled regex)
# comment line            ignored
""                        a doubled quote inside a field stands for one quote

• Empty lines and # comment lines are skipped; a byte-order mark at the start of the file is ignored; (?#…) comments inside a regular expression are removed; a leading ^ before the quote is accepted (the rule is treated as plain).
• Export writes enabled rules as "find" "replace", disabled as "#find" …, regular expressions as "*find" …, and each file row as a # <file name> comment line.
• Editing a file (pen button in edit mode) opens an editor titled with the file name; its button is “Save”, which writes the rules back into the same file. If writing fails: “The file could not be saved. Remove it and add it again to allow saving.”
• If a picked file cannot be read as rules: message “The file could not be read”.

4.3.7 “Pause after” dialog

• Hint: “The voice takes a breath after each of these characters.”
• Toggle tiles: . , ! ? : ; … — ) " (filled = on).
• A text field (placeholder “Pause after”) for any other characters.
• Button “Apply”. Default: no characters.
• Behaviour: the voice makes a short silence after every listed character. The silence gets shorter as the speed goes up. Punctuation that stands alone (e.g. a closing quote) stays with the text before it.

4.3.8 On-page TTS buttons

Shown when “TTS buttons on the page” is on (default), read-aloud is playing or paused and the panels are hidden:

• Drawn as outlines in the status-bar text colour, at 35 % opacity.
• On wide screens (tablets, landscape): small buttons inside the bottom status-bar row.
• On narrower screens: larger buttons in a row just above the status bar.
• Not shown over full-screen pictures or during RSVP playback.
• Reader settings → “Reset” turns this option back on.

4.4 How reading works (engine behaviour)

4.4.1 What is read

• From a selection: starts in the paragraph/sentence where the selection begins, at that word.
• Inline footnotes (EPUB) are read where they occur as *“Note . . End of note."*
• Drop caps are joined back to their word.
• Very long paragraphs are split at sentence ends.

4.4.2 Highlighting and following the voice

• The paragraph being read is highlighted in the chosen “Highlight” colour (EPUB: over the paragraph text, not over footnote markers; PDF: boxes over the sentence).
• The page follows the voice forwards and backwards: when the voice reaches a paragraph that is not visible (or you scrolled away), the view moves to it; a paragraph already on screen is left still.
• Pausing removes the highlight; stepping while paused moves the highlight without speaking.

4.4.3 Automatic page/chapter turn

• After the last paragraph: EPUB-type books open the next chapter; PDF goes to the next page; others turn the page.
• Up to 5 pages/chapters in a row with nothing to read are skipped; after that, reading stops.
• At the end of the book reading stops (the notification goes away).
• If the page text cannot be read, reading pauses.
• If the speech engine reports an error, reading pauses.

4.4.4 Previous / next semantics (important difference between controls)

4.4.5 Resume

Play after pause resumes at the same paragraph if you are still on the same page; otherwise reading restarts from the top of the current page.

4.5 Android media session, notification and headset

4.5.1 Notification

The notification stays while reading is playing or paused and goes away when read-aloud stops.

4.5.2 Media session (lock screen, quick settings media player, Bluetooth, car)

The system media player shows the book title, the chapter (as the artist), “TTS” (as the album) and the cover.

Progress bar: each page counts as 2 minutes, so a 300-page book shows as 10 hours. Dragging the system seek bar jumps to the matching page.

What the system controls do:

4.5.3 Headset and media keys

4.5.4 Audio focus

• While speaking, LibreraX stays the active media app.
• Any interruption — a phone call, a navigation prompt, another player — pauses reading, even a short one. It does not resume automatically.

4.5.5 “Last-read book”

When a command arrives with no book loaded, LibreraX uses the book you read most recently (the first book of the Recent shelf).

4.6 iOS Now Playing, lock screen and remote commands

• Reading continues with the screen locked or the app in the background.
• Now Playing shows the book title and the chapter (as the artist). There is no cover art and no progress bar or seeking on iOS.
• Remote commands (lock screen, Control Center, AirPods/headphones, CarPlay):

• On iOS, very high or very low speeds are limited to what Apple’s voices support; pitch is 0.5–2.0.

4.7 Android home-screen widgets

All three widgets go on the home screen only and can be resized in both directions. They refresh every 30 minutes, when the library changes (scan, progress, tags, favourites) and whenever you leave the app.

Removing a Shelf or Book widget deletes its settings.

4.7.1 Shelf widget

Setup screen (popup titled “Widget”, cannot be closed without choosing, button “Apply”):

Display:

• Rounded background; the text turns dark on light backgrounds automatically.
• Grid: as many columns of covers as fit; with “Fit covers to widget height” the covers fill the widget height (one row).
• List: small cover + title (up to 2 lines).
• Books without a cover: dark tile with the first two letters of the title.
• Order: “Reading Now” and “Recent” by last-read time (newest first); other shelves and tags by the library’s current sort order and direction.
• Empty shelf: shows “Librera X”; tapping opens the app.
• Tap a book: opens it at the last position.

4.7.2 Book widget

• Shows one book cover (cropped, slightly rounded corners); without a cover, a dark tile with the title (up to 4 lines).
• Setup popup “Book”: a search field (placeholder “Find”) and the library list (most recently read first, up to 200 books) with cover, title and author; tap a book to pick it.
• Setup is optional: if skipped, the widget shows the most recently read book and follows it.
• Tap: opens the book where reading stopped.
• Add a widget for a specific book directly: book menu item “Add widget to home screen” (phone icon), also available as a phone icon in the book’s details. The launcher’s dialog shows a cover preview; the new widget shows that book.

4.7.3 Read-aloud (TTS) widget

• Layout: cover on the left, then title (bold, sized to fit), author, chapter, “page / pages”, and three round buttons: previous, play/pause (filled blue), next.
• When the widget is resized small: no cover, the title on one centred line, and the buttons.
• Colours: translucent dark background, light-blue accent.
• Content: the book currently loaded for read-aloud, otherwise the most recently read book (its saved chapter and page). With no books: “Librera X”.
• Tapping the title or cover opens the book.
• Buttons when a book is loaded for read-aloud: previous/next paragraph (crossing pages), play/pause.
• Buttons when nothing is loaded: Play starts reading the last book without opening the reader (background reading, §4.2.1); previous/next do nothing useful until a book is loaded.
• Updates live with play/pause, page and chapter changes.
• Add it from the TTS dialog menu: “Add widget to home screen”.

4.8 iOS home-screen widgets

The widgets update whenever the library changes or a scan finishes. They do not refresh on their own.

Available shelves: “Recent” (by last read), “Favorites” (by last read), and up to 20 tags (each sorted by last read); up to 8 books per shelf.

Display:

• Book, Small: cover filling the widget with a reading-progress bar along the bottom.
• Book, Medium: cover + title (up to 3 lines), author (in accent blue), progress bar.
• Shelf: header with the shelf name in accent blue; Medium = 4 covers in one row, Large = 8 covers in two rows.
• Missing cover: coloured tile (colour depends on the title) with the title in white serif.
• Empty: “Nothing here”.
• Background: dark navy; accent light blue.
• Tap (the whole Book widget, or each cover in Shelf): opens the book in LibreraX.
• There is no read-aloud widget on iOS.

4.9 Watch apps

4.9.1 Wear OS (Android)

• Companion app “Librera X” for Wear OS. It does not work on its own — it needs the phone app.
• One screen:
  • Time at the top; a circular progress ring around the edge (progress through the book).
  • Cover thumbnail, title (up to 2 lines), chapter (or pages if no chapter), and pages on a third line when both exist.
  • Buttons: “Previous page” (small), Play/Pause (large), “Next page” (small), and “Stop” (small; only while speaking or paused).
  • Before the phone has sent anything: “Open a book on your phone”.
• The watch shows the book being read on the phone and updates on every change; when nothing is being read, it shows the most recently read book.
• The buttons control every connected phone:

4.9.2 Apple Watch

• watchOS app “LibreraX” (watchOS 10 or later), companion of the iPhone app.
• Screen: cover, title (2 lines), chapter or pages, pages; a progress bar; buttons previous, play/pause, next, and stop (only while speaking or paused). VoiceOver labels: “Previous page”, “Play”/”Pause”, “Next page”, “Stop”.
• While waiting for the phone: a spinner (up to 3 s), then “Open a book on your phone”.
• The watch updates whenever playback or the library changes on the iPhone, and asks for fresh data when it reconnects.
• Buttons work only while the iPhone is in reach:

4.10 Cars

4.10.1 Android Auto (PRO edition only)

• LibreraX appears in Android Auto as a media app only in the PRO edition. The free edition does not appear in Android Auto.
• Browsing:
  • Two lists: “Recent” and “Favorites”.
  • “Recent”: recently read books, newest first. “Favorites”: favourites in the library’s sort order.
  • Up to 50 books per list, each with title, author and cover (shown as a grid).
• Selecting a book opens it on the phone and starts reading aloud.
• Voice: “play " searches the library and reads the best (most recently read) match.
• Play, pause, next, previous and the progress bar work as in §4.5.2.

4.10.2 CarPlay (iOS)

CarPlay is not available in the App Store builds yet: Apple has not yet given LibreraX permission to appear in CarPlay. When it becomes available, it works like this:

• One list titled “LibreraX” (tab icon: books).
• Lists the 12 most recently read books: cover, title, author, a progress bar, and a playing indicator on the book currently loaded.
• Tapping a book plays it (resumes if already loaded, otherwise opens it on the phone and starts reading) and shows the CarPlay Now Playing screen (controls as in §4.6).
• The list refreshes when the app becomes active.

4.11 Automation (Android)

Automation apps such as Tasker or Automate, and launcher shortcuts, can control read-aloud without opening the app: start or resume reading (the current book, a chosen book, or the last book read), play/pause, pause, stop, and move to the previous or next paragraph. Nothing appears on screen; the command just runs.

4.12 Opening books from other apps, “Open with” and sending

4.12.1 Android: LibreraX as a book viewer

LibreraX appears in the “Open with” list of other apps (file managers, browsers, mail, messengers) for these files:

• EPUB
• PDF
• MOBI, AZW, AZW3 (also KF8 and PRC)
• FB2 (also zipped FB2)
• CBZ and CBR comics
• Plain text, Markdown, HTML and XHTML
• Word documents (DOC, DOCX) and RTF
• DjVu (read through Librera PRO)

Files are also recognised by their extension, and an EPUB sent as a ZIP file still opens as a book.

If you chose LibreraX as the default “open with” app in an older version, that choice keeps working.

Behaviour:

• A book shared from another app that LibreraX cannot keep access to is copied into the app first, then opened.
• A book opened from another app returns you to that app when you close it.

4.12.2 iOS: document types and URL scheme

• “Open in…” / “Share to LibreraX” works for: EPUB, PDF, FB2, MOBI/PRC, AZW3/AZW/KF8, CBZ, CBR, plain text, Markdown, HTML, XHTML, RTF, DOC, DOCX, ZIP. LibreraX is offered as an alternative app, not as the default.
• Incoming files are copied in (not opened in place), added to the library and opened.
• The app’s Documents folder is visible in the Files app and in Finder on a Mac.

4.12.3 “Open with” and “Send file”

4.13 Integration with Librera (the classic app)

4.13.1 Librera’s “LibreraX reading mode”

When you turn on “LibreraX reading mode” in Librera, books you open in Librera open in LibreraX instead, inside Librera. LibreraX opens the book at the place where you were reading in Librera — even if the page layout is different — and brings along Librera’s bookmarks and notes/highlights for that book, Librera’s scroll or page mode and its full-screen setting.

When you close the book, you are back in Librera, and Librera continues from the place you reached in LibreraX. If the book could not be opened, Librera keeps its old position.

4.13.2 Librera’s “Export to LibreraX”

Choose “Export to LibreraX” in Librera to move your data over. LibreraX shows “Export progress” with a progress bar while it imports reading positions, bookmarks, tags, favourites and highlights, then opens the library. Only the official Librera apps can export to LibreraX. (The in-app “Import from Librera” folder import is described in the library chapter.)

4.14 E-ink devices

On Android, LibreraX recognises e-ink readers automatically when it starts. (There is no automatic recognition on iOS.)

Effect: on the first start, before any theme has been chosen, the app switches to the E-ink style: custom theme, white paper, black accent, fully opaque panels, animations off, and the book uses the first (plain day) page theme. A theme you chose earlier is never changed.

Manual: Settings → theme → “Theme style” chips “Dark” / “White” / “OLED” / “E-ink”. Choosing “E-ink” applies the same preset (animations off); choosing any other style turns animations back on.

4.15 App-wide animation speed

• All animations in the app (menus, sheets, popups) run at one speed:
  • no animation when “Enable animations” is off (or the E-ink style turned it off);
  • otherwise the system Animator duration scale (Developer options; Android 8 and later), so turning animations off in the system settings also turns off LibreraX animations;
  • normal speed on older Android.
• iOS: the status bar hide/show animation also follows “Enable animations”.

4.16 Settings reference (TTS and devices)

Read-aloud settings are the same for all books. Widget settings are kept separately for each widget.

4.17 Platform differences at a glance

Part 5 — OPDS catalogs, cloud sync and editions

Section A covers online catalogs, section B the account, sync and Google Drive books, and section C the FREE / PRO 3H / PRO / PRO+ editions, advertising, subscriptions and licences.

5.A OPDS catalogs

5.A.1 Where OPDS lives in the app

• OPDS tab (bottom tab bar, globe icon). It is hidden by default on both platforms (on iOS the Folders tab is hidden too). It can be shown in the tab settings, or from the OPDS page menu item “Show OPDS tab” (see 5.A.9).
• “OPDS” pill in the Library chip bar (globe icon, label “OPDS”), left of the shelf chips:
  • Tap → opens the OPDS browser inside the Library screen, starting on Project Gutenberg’s popular page (or on the page you pinned, see 5.A.12). The Library search icon then searches the catalog.
  • Long-press → shows the OPDS tab (turns it on if hidden) and switches to it.
  • The pill can be turned off in Library shelf settings: switch “OPDS” (default on). Turning it off also unpins the “Free books” strip and turns that strip off (see 5.A.12).
• “Free books” strip in the Library (see 5.A.12) — tapping it also opens the OPDS browser inside the Library.
• The globe icon in the OPDS title bar: on a catalog page it goes back to the catalog list; on the catalog list it goes to the Library (Home).

5.A.2 Built-in catalogs

Default order: catalogs for any language, or in the device’s system language, come first (in table order); the other-language catalogs follow. Your own catalogs come after the built-in ones. Once you reorder the list, your order is remembered; catalogs that are not in it yet go to the end.

5.A.3 Catalog list screen

Each row shows:

• the catalog’s own icon (filled in automatically for catalogs you add) — or a round accent badge with the first letter of the name;
• name (bold) and a second line “subtitle · host”;
• a ⋮ button. Long-press on the row opens the same menu.

Row menu: “Edit” (catalogs you added only) and “Remove”.

• Removing a built-in catalog hides it immediately (no confirmation).
• Removing a catalog you added asks “Remove %1$s from the catalogs?” → “Remove” (red) / “Cancel”. The saved login for that server is forgotten too, unless another remaining catalog uses the same server.

Bottom of the list: “Add catalog” button; and, only when at least one built-in catalog is hidden, “Restore the built-in catalogs” (shows all built-in catalogs again; catalogs you added are untouched).

Top bar on the catalog list: ”+” (Add catalog) and ⋮ with:

• “Reorder” (check mark while active) — shows a drag handle (≡) on every row; drag a row up/down, the list scrolls by itself at the edges; the order is saved when you let go. Tap “Reorder” again (or Back) to leave.
• “Proxy server” — label becomes “Proxy server · host:port” and is checked while a proxy is active (5.A.8).
• “Restore the built-in catalogs” — only when something is hidden.

5.A.4 Adding / editing a catalog

Popup title “Add catalog” (or “Edit catalog”). Fields, top to bottom:

If the address you type is not a catalog itself, LibreraX tries the common catalog addresses on that site.

Behaviour:

• Save without a successful Verify first runs Verify and saves only if a catalog is found. Editing a catalog without changing the address saves immediately.
• On success the address field is replaced by the address actually found; an empty Name or Description is filled from the catalog’s own title and subtitle, and its icon is kept.
• A newly added catalog opens immediately after saving.
• Name, subtitle and icon of a catalog you added are also filled in automatically the first time it opens, if they are still blank.
• The login and password typed here are remembered for that server (5.A.7). Clearing the login field when editing forgets the saved login for that server.

5.A.5 Browsing a catalog

• Breadcrumbs strip under the top bar: “Catalogs” chip, then one chip per opened page (titles longer than 32 characters are cut with “…”); the current page is highlighted. Tapping a chip goes back to that level.
• Back cancels a page that is still opening, else closes the search row, else goes up one page.
• A thin progress bar under the top bar while a page is opening or loading.
• Navigation entries (folders/categories): folder icon or the entry’s thumbnail, bold title, up to two lines of description, chevron. Entries that lead nowhere are shown greyed and cannot be tapped. While a tapped entry is opening it is tinted and shows a small spinner.
• Book entries depend on the display mode (display picker in the top bar; default List):

Navigation entries always span the full width. The format line lists the formats you can download, e.g. EPUB PDF FB2. When the OPDS browser is shown inside the Library it uses the Library’s display mode.

• Covers: a small image is used in lists, the full cover in grids and the book sheet. If there is no image, or covers are turned off in the app, a drawn cover (format + title + author) is shown. Project Gutenberg books without an image get Gutenberg’s own cover automatically.
• Endless scrolling: the next page loads automatically as you near the end of the list; a spinner row shows at the bottom; on failure “Could not open: %1$s” with “Try again”.
• Empty page: “Nothing here”. Failed page: “Could not open: %1$s” + “Try again”.
• Single-book shortcut: when a navigation entry leads to a page that holds only one book (for example a Gutenberg page for one book in several formats), the book sheet opens directly, with all download links together.
• Facets (the catalog’s own filters and sort orders): a horizontally scrolling chip row below the top bar. If there is one group with up to 5 choices they are shown as chips (group name first); otherwise each group is one chip “Group: active value” that opens a menu. Choosing a facet replaces the current page (it does not add a breadcrumb).
• Extra sections: links the catalog offers for the whole page (such as popular, new, featured, recommended or collections) that are not already in the list are added as navigation entries at the end.

Error texts: “Could not open: %1$s”, where the reason is “this address is not an OPDS catalog”, “%1$s asks for a login”, “HTTP ", or the network error.

5.A.6 Search

• A search icon appears in the top bar when the current page, or any page above it in the breadcrumbs, can be searched. Tap → the search row slides down: hint “Find in %1$s” (catalog name), arrow button (appears when text is typed) or the keyboard’s Search key, ✕ to close.
• The search uses the nearest page that offers search.
• The result opens as a new page titled “Found: %1$s”. Closing the search row with ✕ clears the query and returns to the page where the search was started.
• If the catalog’s search cannot be used: “Could not open: this catalog cannot be searched”.

5.A.7 Login / authentication

• When a catalog asks for a login, the “Log in” popup appears: “%1$s asks for a login” (host), the server’s own message if any, “Login”, “Password”, “Save”. Saving repeats what needed the login (opening a page, searching, downloading). Saving with an empty login forgets the saved login.
• Supported: Basic and Digest login.
• Logins are remembered per server on this device only; they are not synced.
• Download links that need DRM or account-based lending are hidden (see 5.A.10).

5.A.8 Proxy server (OPDS only)

Popup “Proxy server” (from the ⋮ menus):

• The proxy is used on Android, only when it is switched on and the server and port are valid. On iOS the setting is shown but catalogs connect directly. The menu items show “Proxy server · host:port” with a check mark while it is active. Saving takes effect immediately.

5.A.9 Page menu (inside a catalog)

Top bar on a catalog page: search icon (when available), display picker, ⋮ with:

• “Reload” — opens the page fresh from the catalog and tries failed covers again.
• “Proxy server” / “Proxy server · host:port”.
• “Add catalog”.
• “Show on library screen” (pin icon, checked when this page is the Library’s “Free books” source — 5.A.12).

When the browser is shown inside the Library, the breadcrumb strip ends with a pin icon (toggles “Show on library screen”) and a small ⋮ that also contains “Show OPDS tab” (check box; shows/hides the OPDS bottom tab).

5.A.10 Book details sheet

Opened by tapping a book entry. Title bar = book title. Content:

1. Cover. Tap → full-height cover; tap again to return.
2. Title (up to 5 lines), author(s), and a facts line “year · LANGUAGE · publisher”.
3. Section “Download” — one row per file offered:
   • format badge (EPUB, PDF, MOBI, AZW3, FB2, FB2.ZIP, CBZ, CBR, TXT, MD, HTML, XHTML, ZIP, RTF, DOC, DOCX, ODT, DJVU, LRF, CHM, or the file’s extension);
   • the link’s own title (e.g. “EPUB (no images)”) or the format;
   • size (when the catalog gives it); while downloading, “done / total” and a progress bar (a moving bar if the size is unknown);
   • right side: download arrow → ✕ while downloading (tap the row to cancel) → “OPEN” button once the file is there.
   • No files: “The catalog offers no file of this book to download.”
4. Info table (only filled rows): “Language”, “Publisher”, “Publication Date” (date only), “Categories” (comma-separated).
5. “Description” — formatted text with clickable links (accent colour); images removed.
6. “See also” — related catalog pages; tap opens that page.
7. “Web page” button (globe) — opens the book’s web page in the browser.

Links to buy, borrow or subscribe, and DRM-protected files, are not shown.

5.A.11 Downloads

• Where books go: an OPDS folder in the app’s own storage.
  • Android: Android/data/<app>/files/OPDS (inside the phone’s storage if there is no external storage);
  • iOS: inside the app’s private storage. You cannot choose this folder. It is added to the library folders automatically after the first download.
• File name: the book title (up to 80 characters; “book” if there is no title), with the right extension for the format. If the name is taken, “ (1)”, “ (2)”, … is added.
• A failed or cancelled download leaves no file behind.
• Several downloads can run at once; the same link cannot be started twice.
• After download: books in a supported format are added to the Library and their details are read; toast “Downloaded: %1$s”. Other files: toast “Saved to %1$s” (folder path).
• “OPEN”: supported formats open in the reader (closing the sheet); other files go to the system “Open with”.
• LibreraX remembers which link gave which file; “OPEN” is shown as long as the file still exists.
• Failure: “Download failed: %1$s”; if the catalog asks for a login during a download, the login popup appears and the download is tried again (in the Library’s “Free books” sheet a login error is shown as a toast instead).

5.A.12 “Free books” strip (Discover / popular books)

• Shown in the Library when the strip is on (default on):
  • as a header on the All shelf (no tag filter) when the library has books;
  • at the top of the Library when the library is empty and not scanning.
• Header: arrow button + label — “Free books”, or the title of the pinned page. Below it a horizontal row of up to 10 covers.
• Source (default): Project Gutenberg’s popular books https://www.gutenberg.org/ebooks/search.opds/?sort_order=downloads. The last copy is shown immediately, then the fresh list replaces it.
• Offline / first start: a copy that comes with the app, with 10 Gutenberg books and their covers: Pride and Prejudice, Moby Dick; Or, The Whale, Frankenstein, Alice’s Adventures in Wonderland, The Adventures of Sherlock Holmes, Chambers’s Twentieth Century Dictionary part 1, Romeo and Juliet, The Complete Works of William Shakespeare, Dracula, Crime and Punishment. These covers are also used for those books when the live list is shown.
• Tap the header → opens the OPDS browser inside the Library with Gutenberg (its first page + the popular page, or the pinned catalog + pinned page). Tap a cover → the book sheet; if the book cannot be found, the browser opens at that entry.
• Pinning: on any catalog page, “Show on library screen” (or the pin icon) makes that page the strip’s source; its title becomes the strip label. Turning it off on the pinned page hides the strip. Pinning the Gutenberg popular page itself just restores the default source.

5.A.13 OPDS preferences summary

5.B Cloud and sync

5.B.1 Overview

“Cloud” in LibreraX is two things:

1. Your reading data — positions, favourites, read marks, tags, the Recent list, bookmarks, highlights and notes, kept in LibreraX’s cloud for your account. You sign in with Google (Android, iOS) or Apple (iOS).
2. Google Drive — the book files themselves, in the folder LibreraX/Books (covers in LibreraX/Covers). Access is limited: “LibreraX sees only the files it has put there itself.”

Intro text when signed out: “Keeps progress, favourites, tags and notes the same on every device, and connects Google Drive for your books”.

5.B.2 Where the account is managed

• Settings → “Google account” card (always).
• Cloud tab when signed out shows the same section centred on the screen.

Signed out

• Note text (above).
• iOS only: Apple’s “Sign in with Apple” button (black on light theme, white on dark).
• “Sign in with Google” button (Google “G” logo, Google’s colours: white on dark theme, black on light).

Signed in

• Header “Google account” with a small “Sign out” button on the right.
• Account row: user icon, email (or name), status line: “Syncing…”, “Sync failed: %1$s”, or “Synced %1$s” (how long ago). A chevron (and tapping the row) opens the data panel:
  • “What is synced” button → dialog (5.B.8);
  • explanation: “Deletes everything LibreraX keeps for this account in its cloud: reading positions, bookmarks, notes, favourites, tags and read marks. Books on your Google Drive are not touched or deleted. The library on this device stays as it is, and this device stops syncing. Other devices signed in to this account keep their own copy.” + “Your LibreraX sign-in account is deleted too. You may be asked to sign in once more to confirm it is you.”;
  • red “Delete account” button (spinner while deleting).
• iOS, signed in with Apple but no Google linked: “Continue with Google” button + text either “Google Drive connects through the Google account with the same email, %1$s. No Google account for this email yet? Create one at accounts.google.com — any email works, not only Gmail — then tap “Continue with Google”.” or, for Apple’s hidden email, “Your Apple ID hides its email, so choose the Google account you use for Google Drive and on Android.”
• iOS, signed in with Google but no Apple linked: an Apple “Continue” button to link the Apple ID.
• Errors appear in red under the section (cancelling a sign-in shows nothing). Wrong Google account picked during linking: “%1$s is a different email. Google Drive connects only through the Google account %2$s — choose it, or create a Google account for this email at accounts.google.com.”

5.B.3 Sign-in methods and platform differences

After a successful sign-in a first sync runs; then Google Drive access is asked for (Google accounts), or Google is linked first (Apple-only accounts).

5.B.4 What is synced

• Reading position and progress in every book
• Favourites (hearts) and the Recent list
• Read and unread marks
• Tags
• Which books are in the library and which are removed from it
• Bookmarks, highlights, notes and PDF annotations, including deletions
• Which books are kept on your Google Drive

Not synced: the book files themselves (those go through Google Drive, 5.B.7), app settings, OPDS catalogs and logins, and reader appearance.

A book is recognised by its content, not by its name or folder: the same file in different folders or on different devices is the same book, and a changed file counts as a new book.

5.B.5 How syncing works

A sync brings in the changes made on your other devices, sends the changes made on this one, and downloads or refreshes books from Google Drive (5.B.7). The account row then shows “Synced ", or "Sync failed: …".

When two devices changed the same book:

• Each kind of data (favourite, Recent, position, read mark, library) is handled on its own and the newest change wins. A heart set on the phone and a position reached on the tablet are both kept.
• Tags are merged one by one: the newer change wins.
• Bookmarks and notes: the newest change wins, and deleting one on a device deletes it on the others.
• All devices end up the same.

Data for a book that is not on this device yet is kept and applied as soon as the book arrives, for example after you copy the file over or download it from Google Drive.

5.B.6 When syncing happens

• “Sync automatically” (⋮ on the Cloud screen; default off) works only in PRO+. In any other status tapping it shows: “Sync automatically is available only with PRO+ (a subscription). Press Sync to sync now.” Manual sync is available to everyone who is signed in.
• After sign-in the account is synced right away; restoring a backup starts sync again.

5.B.7 Google Drive — LibreraX/Books

Upload

• “Upload to Cloud” (cloud icon) in a book’s menu, and an upload action in the Library and Cloud selection bars (hidden when every selected book is already in the Cloud).
• The file is uploaded to My Drive/LibreraX/Books/<file name> (folders are created when missing) and its cover to LibreraX/Covers/<file name>.jpg. Books upload one at a time.
• Uploading a book that is already in the Cloud replaces that Google Drive file instead of making a copy.
• A PDF changed in the reader (annotations written into the file) is uploaded again automatically when the book is closed, if it was in the Cloud.
• Toast “Uploaded to Cloud”, or the first error, e.g. “Sign in with Google in the Cloud tab first”, “Use only Wi-Fi is on: connect to Wi-Fi first”.

Download

• Tapping a book that is only in the Cloud downloads it (status “Downloading 1 of 1 · name”) into the download folder and opens it.
• Automatic downloads during every sync: books that another device uploaded, that are missing here, and that are still in this account’s LibreraX/Books are downloaded into the download folder. Files in the Google Drive trash and older uploads are never fetched.
• Refresh: during a sync, a book downloaded earlier into an app folder is replaced when the Google Drive copy is newer and has a different size (e.g. a PDF annotated on another device).
• When there are several copies of a book on the device, opening it picks the copy whose size matches the Google Drive version.
• The download folder is added to the library folders and scanned again after downloads.

Download folder

• ⋮ → **“Download folder: "** opens a folder picker. Default **"The app's own folder"**:
  • Android: Android/data/<app>/files/Books;
  • iOS: Documents/Books.
• When you have chosen your own folder, an extra item “The app’s own folder” resets it. If the chosen folder can only be read: “The download folder was attached for reading only”. A chosen folder that no longer exists falls back to the app’s own folder.

Hide Cloud books in Library

• ⋮ → “Hide Cloud books in Library” (default on): books inside the download folder are hidden from the Library shelves (they still appear in the Cloud tab, and in the Library when filtering by a tag).

Delete

• Delete dialog: “Delete from the device? The files cannot be brought back.” with a checkbox “Also delete from the Cloud (to Google Drive trash)” for books that are in the Cloud (checked by default when deleting from the Cloud screen, unchecked elsewhere). It moves the book and its cover to the Google Drive trash; the file on the device is deleted (books that are only in the Cloud just lose the Google Drive copy).

5.B.8 “What is synced” dialog

Title “Cloud”:

• Google Drive (account email): “Books” count (from the last Cloud listing) + “The book files themselves, in LibreraX/Books on your Google Drive, so any of your devices can download them.”
• Google Cloud (account email): “Books” count + long note (“One record for each book you have opened or marked on any of your devices: where you stopped reading, the heart, the read mark, tags and the recent list. … The book files are not stored here.”), “Reading positions”, “Bookmarks”, “Highlights” counts (counted live; deleted ones are not counted). Spinner while counting; error “Cloud: %1$s”. Button “OK”.

5.B.9 Cloud screen layout

Top bar (cloud icon title → back to Library):

• search icon → filter row (matches title, author, file name);
• display picker: List / Two columns / Grid / Covers (default = the Library’s display, or Two columns);
• sort picker with three options: “Last read” (default), “File Size”, “File modified date”, plus ascending/descending (default descending). Books without a value go last;
• ⋮ menu: | Item | Default | |—|—| | “Sync automatically” (checkbox, PRO+ only) | off | | “Use only Wi-Fi” (checkbox) | off | | “Hide Cloud books in Library” (checkbox) | on | | “Download folder: …” | “The app’s own folder” | | “The app’s own folder” (only when you have chosen your own folder) | — |

Status line under the bar: current work (“Uploading %1$d of %2$d · name”, “Downloading %1$d of %2$d · name”, “Reading the Cloud…”, “Getting covers %1$d of %2$d”, “Syncing…”) or “ books"; errors; second line "Synced %1$s" (green with a check when everything is done); **"Sync"** button on the right; progress bar below.

Body states:

• signed out → the Google account section;
• Google Drive not connected → “The Cloud is LibreraX/Books on your Google Drive. LibreraX sees only the files it has put there itself.” + “Connect Google Drive”;
• “Press Sync to see the books in the Cloud” (manual mode, before the first listing);
• “No books in the Cloud yet. Put one there from its menu: Upload to Cloud.”;
• “Waiting for Wi-Fi” when Wi-Fi only is on and the device is on mobile data;
• “Cloud: %1$s” errors;
• otherwise the book list (same views as the Library). Books not on this device show a cloud-outline corner mark (“In the Cloud, not on this device”) and the title/author/progress/heart/tags known from the cloud. A Subscribe button sits at the top of the list for everyone except PRO+.

Selection mode (long-press books): info (books on the device), tags, heart/unheart, send/share (on the device), delete, remove from library, mark read/unread, reload metadata (on the device), upload (books not yet in the Cloud), open with (one book on the device). For books that are only in the Cloud, heart / tags / read mark / library changes go to the cloud; if the book is not known yet: “Sync the Cloud first to change a book that is not on this device”.

Cloud list refresh: the list of books in the Cloud is remembered and read again after 5 minutes or after changes; in manual mode it is read again only when you press Sync (the first time it is always read once).

5.B.10 Use only Wi-Fi

• Default off. When on and not on Wi-Fi (Android also counts Ethernet), the Cloud list, uploads and downloads wait; the screen shows “Waiting for Wi-Fi”; uploads fail with “Use only Wi-Fi is on: connect to Wi-Fi first”. When Wi-Fi returns, sync starts automatically (with “Sync automatically”).

5.B.11 Account deletion

1. Settings → Google account → open the panel → “Delete account” → dialog “Delete your account?”: “All reading positions, bookmarks, notes, favourites, tags and read marks kept in the cloud for this account will be deleted for good. Books on Google Drive are not deleted. This can’t be undone.” + the note that the sign-in account is deleted too → “Delete” (red) / “Cancel”.
2. If you signed in more than 4 minutes ago, you are asked to confirm it is you (Google: often without a prompt, otherwise the account picker; iOS with Apple: Sign in with Apple always asks).
3. Sync stops and everything kept in the cloud for this account is deleted.
4. This device’s data will be sent to the cloud again if you sign in later; the “Synced” time resets.
5. Your sign-in account is deleted and the app signs out; toast “Your account was deleted”.
   • Books on Google Drive and the library on the device stay.

5.B.12 Sign out

“Sign out” stops sync, signs out (also of Google on that device) and forgets any subscription known from other devices (so PRO+ “from another device” ends on this device). Data on the device stays.

5.B.13 Cloud and sync preferences summary

5.C Editions and monetisation

5.C.1 The four statuses

Rules: the higher status wins (PRO+ > PRO > PRO 3H > FREE).

• Ukrainian = the app’s own language setting, or the phone’s language when the app setting is “System”. The phone language alone does not count if the app is set to another language.
• Librera PRO and Ukrainian count only on the device itself, never through the account, and are never PRO+.
• iOS: the app is FREE; Ukrainian gives PRO; a store subscription gives PRO+.
• Android: there is a FREE app and a PRO app.
• If you uninstall Librera PRO, the PRO status updates; it is also checked again every time you return to the main screen.
• Manual sync needs you to be signed in (any status).

5.C.2 What PRO unlocks (paid features)

In FREE, these actions first play a short video, which gives PRO 3H for 3 hours, and then the action runs:

• If no video is ready (or the last video was less than 5 minutes ago), the feature opens without a video.
• Next to these actions FREE users see a green “PRO ⓘ” note; tapping it opens: “Applying this plays a short video first, then everything is open for 3 hours. Subscribe for %1$s to skip the video.” (tapping the text starts Subscribe).
• “PRO” labels (green “PRO ⓘ” tag, only in FREE) also appear on: the drawing/annotation tool bar, the TTS panel, and the reader’s page-layout menu section with “Speed reading (RSVP)”, “Accent reading”, “Reflow pages”, “Reflow to EPUB”. Tapping a label opens a small offer: a note, Subscribe, and (if a video is ready) “Try PRO for 3 hours”.

5.C.3 Advertising (AdMob)

Ads show only while the status is FREE and at least 3 hours have passed since install, so never in PRO 3H, PRO or PRO+.

5.C.4 Consent (UMP) and tracking (ATT)

• Google’s consent form appears at app start when ads can be shown, and only where the law requires it (EEA, UK and similar).
• iOS: after the consent form, if you have not yet answered, the system “Allow tracking” (App Tracking Transparency) prompt is shown. iOS asks for ads only when the consent allows it.
• “Privacy options” link in Settings → About (shown only while not bought, i.e. FREE/PRO 3H): tap → the privacy options form (to change your consent); long-press → resets consent (toast “Privacy options”); the form shows again at the next start.
• “Privacy Policy” → https://librera.app/privacy.html; “Terms of Use” → https://librera.app/terms.html.

5.C.5 Reward video trial

• “Try PRO for 3 hours” (green button) in the subscription message — FREE only, and only when a video is ready — with footnote “* One short video, and PRO is yours for 3 hours.”
• Also offered from the PRO labels’ offer and by the paid features (5.C.2).
• Watching moves FREE → PRO 3H for 3 hours. About shows “PRO 3H ends at %1$s” (the time).
• The first 3 hours after install are also PRO 3H (no video needed); About shows when they end.

5.C.6 Subscriptions

• A monthly subscription: on Android through Google Play, on iOS through the App Store.
• Button label “Subscribe · %1$s” with the price from the store; until the store answers it shows $0.99.
• Android: Google Play’s payment sheet opens. iOS: Apple’s subscription sheet opens, with Restore purchases and cancel buttons and links to the Privacy Policy and Terms of Service.
• A cancelled subscription keeps working until the end of the paid period.
• After a purchase the status becomes PRO+ immediately.
• “Check subscription” (Settings → About): toast “Asking Google Play…” then “Subscription active — everything is open.” or “No subscription found on this Google account.” It asks the store first, then your other devices (through the account).
• About shows “Paid through %1$s on this device.” (Google Play / App Store) when the subscription belongs to this device.

5.C.7 Cross-platform subscription (through the account)

• A signed-in device with a subscription tells your account about it, and repeats this regularly.
• Your other devices on the same account check at sync start, when the app comes to the front (at most once a minute), and on “Check subscription”. An active subscription on another device makes this device PRO+ — Android ↔ iOS works both ways.
• This device remembers it, so PRO+ keeps working offline for up to 35 days after the subscribed device last reported it. When the subscription ends, the other devices lose PRO+ at their next check.
• Offer footnote: “* Already subscribed on another device (Android or iOS)? Sign in here with an account that has the same email, and the subscription will work here too.”
• Signing out or deleting the account ends the borrowed subscription immediately.

5.C.8 Subscription message (offer card)

Shown at the top of Settings and as a Subscribe button at the top of the Cloud list (hidden in PRO+).

• ✕ on the card folds it to just the Subscribe button until the app is restarted.
• Thank-you text in About when bought: PRO “Bought — everything is open and there is no advertising.”; PRO+ “Subscribed — thank you. Everything is open and the advertising is gone.”
• The Settings title bar shows “LibreraX” + the status badge (green when ads are off).
• About block: “LibreraX " + green check and badge when bought; "PRO 3H ends at …"; "Check subscription"; thank-you; "Paid through …"; "In memory of my old friend"; contact `librera.reader@gmail.com`; `librera.app`; "Privacy Policy"; "Terms of Use"; "Privacy options" (not bought); "Licenses"; App Store and Google Play badges.

5.C.9 In-app update of LibreraX PRO (Android PRO app only)

• Only in the Android PRO app (never on iOS or in the FREE app).
• Setting “Check for updates” / “When the app starts” (default on; shown only where available). Turning it on checks right away.
• At start the app checks LibreraX’s releases on GitHub for a newer LibreraX PRO version.
• If there is one: a card at the top of Settings “Update available” — “LibreraX PRO %1$s is available.” — button “Update” → downloads it (“Downloading…” + progress bar) and opens Android’s installer. Failure: “Download failed: %1$s”.

5.C.10 App review prompts

• Android: Google Play asks you to rate the app when you press Back on the Library tab to leave the app, only after at least 5 starts and at most once every 60 days; the app then closes.
• iOS: the App Store rating prompt is asked for on the same Back-to-leave action (Apple decides whether it is shown and how often).

5.C.11 Licenses screen and third-party list

Settings → About → “Licenses” popup; each row shows name + licence; tapping opens its web page.

LibreraX is closed source; nothing licensed only under GPL, LGPL or AGPL is included. For that reason there are no hyphenation patterns for Czech, Armenian, Indonesian, Latvian, Macedonian and Serbian Cyrillic; Serbian uses the Serbo-Croatian (Cyrillic and Latin) patterns instead. On Android, DjVu is handled by a separate app, not built into LibreraX. The store badges and the Google “G” are unchanged official artwork; Sign in with Apple uses Apple’s own button.

5.C.12 Privacy-relevant facts

• Your cloud data is kept under your own account and only you can read it.
• LibreraX can see only the Google Drive files it created itself.
• OPDS logins and proxy passwords are kept on the device only, never synced.
• Subscription state, the trial, start counters and a borrowed subscription are kept on the device and are not restored from a backup.
• Usage statistics are collected only in copies of the app set up for them; they record offer, subscription and trial events and which screens are opened.
• iOS asks for tracking permission (App Tracking Transparency) only after the consent form.

Part 6 — Settings reference

The complete Settings tab in screen order: every card and option with its choices and defaults, the interface languages and what a backup contains.

Settings is one of the home tabs (tab label “Settings”, cogwheel icon). It is a single vertically scrolling page made of rounded “cards”. Several cards are folding sections: a title row with a chevron; tapping it opens/closes the content. All folding sections start closed every time you open Settings.

6.0 Order of the screen at a glance

6.1 Top bar

What the statuses mean: FREE = with advertising; PRO 3H = the first 3 hours after install, or 3 hours after a reward video; PRO = the PRO build, Librera PRO installed on the device, or the app shown in Ukrainian; PRO+ = an active store subscription (on this device or on another device of the account), and the only status with automatic cloud sync. iOS builds start as FREE.

6.2 “Folders to Scan”

6.3 “Excluded folders”

Shown only when at least one folder is excluded. Long-press an excluded folder to select it; the plus icon in the top bar puts the selected folders back into the library (see 6.1).

6.4 “Library N” and format switches

Header shows “Library” followed by the number of books currently shown in the library. While scanning, a progress bar (it fills up when the total is known).

Format switches, two columns (all on by default):

Rules:

• Switches are filters on which formats the library shows.
• The last remaining format group cannot be switched off (the tap is ignored).
• A group is disabled (greyed) if none of its extensions are supported by this build.
• DJVU (Android): if Librera PRO is not installed the switch shows the note “with Librera PRO”; if installed but too old, “Update Librera PRO”. Tapping opens a bottom sheet “Librera PRO - DJVU” with “To support DJVU, please install Librera PRO. DjVu pages are drawn by Librera PRO’s DjVu engine.” (or the update variant), “Librera PRO 9.6 or newer is required.”, and buttons “Cancel” / “Install Librera PRO” (or “Update Librera PRO”) that open the store. On iOS the DJVU row is not shown.

The same format switches (plus “Hide duplicates”) also appear in the Library screen’s own settings popup “Settings” → “Display” (chips “List”, “Two columns”, “Grid”, “Covers”) and “Formats”.

6.5 “Google account” (cloud sync)

Signed out:

Signed in: