Episteme Reader

A native Android document reader application built with Kotlin and Jetpack Compose.

Overview

Episteme Reader is an offline-first, privacy-focused document and e-book reader that supports PDF, EPUB, MOBI, AZW3, Markdown, HTML, and plain text.

Note: This is the Open Source (OSS) edition of Episteme Reader. The version available on the Google Play Store is built from this core but includes additional proprietary features.

Features

Supported Formats

• Documents: PDF
• E-books: EPUB, MOBI, AZW3
• Text: MD, TXT, HTML

PDF Features

• Viewing Modes: Vertical Scroll and Paginated view.
• Ink Annotations: Draw directly on pages using Pen, Highlighter, and Eraser tools.
• Text Annotations: Add text notes anywhere on the page using system or custom fonts.

E-Book Features

• Parsing: Native parsing for MOBI/AZW3 via libmobi and EPUB via Jsoup.
• Customization: Adjust font size, line spacing, and margins.
• Custom Fonts: Support for importing user-provided font files (.ttf, .otf).

General

• Text-to-Speech (TTS): Read documents aloud using the system TTS engine.
• File Management: Built-in library organization.

Architecture

• UI: 100% Jetpack Compose (Material3).
• Architecture: MVVM with Unidirectional Data Flow.
• Database: Room (SQLite) for metadata and annotations.
• PDF Engine: pdfium-android (Native PDFium bindings).
• EPUB Engine: Utilizes standard WebView for vertical scrolling mode, and a custom rendering engine for paginated mode.
• Mobi Engine: Custom JNI bindings to libmobi.

Building from Source

1. Clone the repository:

   git clone https://github.com/Aryan-Raj3112/episteme.git
   cd episteme

2. Build: Open in Android Studio and run the ossDebug variant, 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 Source Libraries

This project is made possible by the Android open-source ecosystem:

• Core & UI: AndroidX, Jetpack Compose, Kotlinx Serialization
• Document Engines: PdfiumAndroidKt (PDF), libmobi (MOBI/AZW3), Google WOFF2 (Fonts)
• Parsers: Jsoup (HTML/EPUB), Flexmark (Markdown)
• Media & Image Loading: Coil, Media3 (ExoPlayer)
• Utilities: Room (Database), Timber (Logging)

Contributors

• CCerrer - Testing & QA

License

This project is licensed under the GNU Affero General Public License v3.0 (AGPL-3.0). See the LICENSE file for details.

Support

If you find Episteme Reader useful and want to support its development, please consider sponsoring. Thank you!