* Implement build profiles and feature policy for offline desktop builds * Introduce unified cross-platform Settings Hub * Refactor main settings into a hierarchical page-based navigation model * Refactor library projection to use shared multiplatform logic * Refactor UI state consumption by removing intermediate screen models * Introduce AndroidSharedStateBridge to centralize state mapping and reduction logic * Refactor state management for tabs, selection, and pinning to use shared bridge logic * Refactor file type management and validation into a centralized shared module * Centralize file type resolution and improve handling of unknown types * Centralize book import logic with SharedImportPlanner * Refactor magnifier geometry logic and coordinate mapping * Properly handle orientation changes in scroll-locked PDF reader * Add screen orientation controls to EPUB and PDF readers * Implement right-to-left (RTL) pagination support and refactor reader menus * Separate right-to-left pagination settings for PDF and EPUB * Ensure PDF page data is scoped by document key for multi tab support * Implement theme-aware link styling for the epub reader * Implement jump history for back and forward navigation in the epub reader * Improve locator handling and navigation logic in paginated reader mode * Implement stable pagination navigation and location tracking * Centralize banner message management and auto-dismiss logic in MainViewModel * Implement zoom and pan state preservation for PDF pan lock mode * Enhance reader navigation UI and workspace layout management in desktop app * Refactor reader navigation sidebar and relocate search controls in desktop app * Enhance reader UI with redesigned selection menus and bottom sheet overlays * Implement custom highlight palettes and reader theme customization in desktop app * Implement cross-platform modal layer and refine reader UI styling * Improve highlight accuracy and implement metadata enrichment on book open in desktop app * Implement two-page spread layout for paginated reader on desktop * Implement persistent caching for book loading and pagination in desktop app * Implement persistent caching for book loading and pagination in desktop app * Optimize reader settings updates by separating layout and appearance changes in desktop app * Improve desktop window branding and native Windows styling * Enhance reader selection interactions and UI across EPUB and PDF viewers in desktop app * Refine selection handle positioning and interaction logic * Implement EPUB selection debug logging and improve handle targeting * Optimize desktop book loading performance and UI responsiveness * Implement anchored zoom gestures and rendering optimizations for the Desktop PDF viewer. * Implement smooth zoom preview for the PDF reader in desktop app * Optimize PDF rendering performance and responsiveness in the desktop reader * Implement conditional diagnostic logging and update desktop build configuration * Implemented hierarchical TOC, custom scrollbars, and improved desktop modal handling * Added management options for annotations and highlights in the sidebar in desktop app * Implemented `SharedStableOutlinedTextField` and updated text input fields to use `TextFieldValue` for improved cursor and selection stability. * Refined library filters and enhanced OPDS functionality in desktop app * Improved EPUB pagination measurement and implemented layout diagnostic logging for desktop app * Added PPTX support including document parsing, rendering, and indexing * Improved PPTX rendering and layout accuracy * Implemented text autofit support for PPTX rendering * Enhanced PPTX rendering with support for custom geometry, automatic numbering, table styles, and image opacity * Improved EPUB pagination accuracy and added layout telemetry in desktop app * Improved folder synchronization with metadata-only mode and hashed sidecar management in desktop app * Implemented rich text font scaling and migrated desktop ink tools to custom pointer input handling * Implemented billing account obfuscation * Implemented hierarchical folder navigation and improved library selection functionality in desktop app * Implemented platform-aware directory resolution and multi-platform native library support for desktop * Added full-screen mode for the reader workspace * Added PDF zoom indicator and interactive vertical scrollbar with page tooltips * Refactored speech bubble prefetching to use a limited radius and improved ML detector initialization and lifecycle management * Updated PDF indexing to replace existing page text and removed search result item keys * Implemented "preparing" foreground notification for TTS service * Optimized PDF rendering performance by pre-calculating page-specific annotations * Refactored desktop packaging tasks and improved distribution configuration * Optimized EPUB parser memory usage and added path traversal protection * Refactored WorkManager monitoring logic and added work pruning * Implemented comprehensive resource cleanup and memory management for WebView-based components to prevent memory leaks * Implemented bitmap size limits and scaling to prevent canvas rendering errors * Split long text paragraphs into multiple semantic blocks during HTML parsing * Implemented local ActionMode for text selection to prevent platform crashes * Refactored PPTX text layout, optimized HtmlParser block detection, and improved banner dismissal logic * Added desktop startup splash screen and deferred WebView initialization * Reorganized settings hub and added separate PDF reader defaults * Implemented embedded cover extraction and metadata support for MOBI and FB2 formats * Implemented batching for MetadataExtractionWorker and optimized EPUB metadata extraction performance. * Implemented procedurally generated book covers and replaced static placeholders * Redesigned search UI with a top bar and results overlay in desktop app * Added PDF page gap and overlay visibility options and implemented DesktopBookImporter * Refactored PDF reader UI with tabbed inspector and improved theme background handling in desktop * Implemented PDF viewport persistence for zoom and scroll positions in desktop app * Improved desktop fullscreen implementation and state restoration * Implemented desktop window state persistence * Implemented flavor-based branding and ProGuard configuration for desktop builds * Implemented precise reader positioning and improved highlight rendering logic in desktop app * Added support for user-editable book metadata * Enhanced book metadata support and integrated info/edit dialogs * Implemented embedded EPUB metadata editing * Improved highlight mapping and added custom scrollbar styling for the reader. * Reduced desktop WebView bundle size by excluding unused locales and runtime files * Added neutral pan mode as the default PDF interaction state. * Refactored library empty states and updated primary navigation tabs in desktop app * Implemented native paginated reader and unified content rendering architecture in desktop epub reader * Implemented native EPUB image rendering for desktop and improved block layout spacing with margin collapsing. * Improved pagination overflow detection in desktop * Implemented multi-block text selection with interactive handles and CFI support in desktop epub pagination |
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| CLA.md | ||
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Episteme Reader
A modern, offline‑first, privacy‑focused document & e‑book reader for Android, built with Kotlin and Jetpack Compose.
Overview
Episteme Reader is a comprehensive, customizable reader for documents and e-books on Android. It features a modern Jetpack Compose UI, powerful reading tools, and extensive theming.
To best serve different user preferences regarding privacy and network usage, Episteme Reader is available in three distinct editions:
- PlayStore Version: The full-featured release which includes proprietary code and features.
- OSS Version (GitHub/F-Droid): A fully open-source build.
- OSS Offline Version (GitHub): A strictly offline build with network permissions completely removed.
Feature Comparison
📚 Supported Formats
| Feature | PlayStore | OSS | OSS Offline |
|---|---|---|---|
| Documents: PDF, DOCX, ODT/FODT | ✅ | ✅ | ✅ |
| E-books & Text: EPUB, MOBI, AZW3, FB2, MD, HTML, TXT | ✅ | ✅ | ✅ |
| Comics: CBZ, CBR, CB7 | ✅ | ✅ | ✅ |
| View-Only: CSV, TSV, JSON, XML, Logs, Code Files | ✅ | ✅ | ✅ |
📖 Core Reading Experience
| Feature | PlayStore | OSS | OSS Offline |
|---|---|---|---|
| Display Modes: Paginated & Vertical Scroll | ✅ | ✅ | ✅ |
| PDF Multi-Tab Reading & Reflow | ✅ | ✅ | ✅ |
| PDF Annotations: Ink (Pen, Highlight, Erase) & Text | ✅ | ✅ | ✅ |
| App-wide Customization & Reader Theming | ✅ | ✅ | ✅ |
| Custom Fonts: Local Import (TTF and OTF) | ✅ | ✅ | ✅ |
| Typography Control | ✅ | ✅ | ✅ |
| Auto-Scroll & Musician Mode | ✅ | ✅ | ✅ |
| System Text-to-Speech (TTS) | ✅ | ✅ | ✅ |
⚙️ Advanced & Network Features
| Feature | PlayStore | OSS (F-Droid) | OSS Offline |
|---|---|---|---|
| Local Folder Sync & Library Management | ✅ | ✅ | ✅ |
| Download Google Fonts | ✅ | ✅ | ❌ |
| OPDS Catalog Support | ✅ | ✅ | ❌ |
| PDF Bubble Zoom Magnifier | ✅ | ❌ | ❌ |
| ML Kit OCR (Scanned PDF Text Selection) | ✅ | ❌ | ❌ |
| Cross-Device Cloud Sync | ✅ | ❌ | ❌ |
| AI Tools (Summaries, Story Recap, Dictionary) | ✅ | 🔜 | ❌ |
| Cloud Text-to-Speech | ✅ | 🔜 | ❌ |
Building from Source
-
Clone the repository:
git clone https://github.com/Aryan-Raj3112/episteme.git cd episteme -
Build:
- Open in Android Studio and run the
ossDebugorossOfflineDebugvariant, or - Build from the command line:
./gradlew assembleOssDebug
The APK will be generated at:
app/build/outputs/apk/oss/debug/Episteme-oss-v{version}-oss-debug.apk - Open in Android Studio and run the
Open Source Libraries
Powered by the Android OSS ecosystem:
- Core & UI: AndroidX, Jetpack Compose, Kotlinx Serialization
- Document Engines: PdfiumAndroidKt (PDF), libmobi (MOBI/AZW3)
- Parsers: Jsoup (HTML/EPUB), Flexmark (Markdown)
- Media & Image Loading: Coil, Media3 (ExoPlayer)
- Utilities: Room (Database), Timber (Logging)
Contributors
| Contributor | Contribution |
|---|---|
| Testing & QA | |
| Translation (German) | |
| Translation (Turkish) | |
| Translation (Arabic) | |
| Translation (Russian) | |
| Translation (French) |
Translations
Help translate Episteme Reader into your native language! Weblate is used to manage localization.
License
Licensed under the GNU Affero General Public License v3.0 (AGPL‑3.0). See the LICENSE file.
Support the Project
Help make Episteme Reader even better:
- ❤️ Support on Patreon
- ⭐ Star the repository to help visibility
- 🐞 Report bugs or request features via GitHub Issues
- 💬 Share feedback in Discussions
- ✍️ Leave a review on the Google Play Store
- 📣 Tell a friend!

