# Sutra

> Sutra is an offline-first, native iOS and Android reader app for DRM-free digital books, manga, and comics. It connects directly over local networks or VPNs to self-hosted personal media servers and generic OPDS catalogs.
>
> [Full Context Architecture and Changelog Details](https://sutra-reader.com/llms-full.txt)

Free version includes full EPUB and PDF rendering, automatic series stacking, custom collection management, highlights, reading stats, and localized dictionary lookup. Sutra Pro is a one-time, platform-specific in-app purchase that permanently unlocks native Komga server integration, full .cbz comic reading, and DRM-free .mobi books. No tracking, analytics, cloud middle-men, or subscription fees.

## Capabilities and Restrictions
- **Supported Formats:** EPUB, PDF, CBZ (Pro/Preview), MOBI (Pro/Preview).
- **Unsupported Formats:** CBR archives and DRM-protected files (Kindle AZW/KFX).
- **Integrations:** Kavita, Komga (Pro), Calibre Content Server, Calibre-Web, Calibre-Web-Automated, WebDAV (Synology NAS/Nextcloud), Grimmory, Booklore, BookOrbit, OPDShelf.
- **Built-in Catalogs:** Project Gutenberg (75,000+ public domain volumes), Standard Ebooks (Typeset collection with Patrons Circle support).
- **Core Features:** Guided Panel Mode (one panel at a time), right-to-left manga formatting, dynamic auto-scrolling, inline footnotes, E-ink display mode (Android).
- **iPhone Duo (iOS 2.5.0+):** Two-page facing spreads on the inner display for EPUB, PDF and comics, a page curl that follows the finger, Panel Mode on the outer, inner and folded displays, and a layout that adjusts as the Duo folds. iPhone and iPad are unchanged.
- **Data & Syncing:** Reading progress and completion status sync natively to Kavita and Komga servers. iCloud supports cross-device synchronization on iOS; Android supports manual offline data exports for portability.

## About and Product Information

- [About Sutra](https://sutra-reader.com/about.html): Sutra's reading approach, supported content, and ways to get help or share feedback.
- [iPhone Duo](https://sutra-reader.com/iphone-duo.html): Two-page spreads on the inner display, Panel Mode on every screen, and a layout that adapts as the Duo folds, in Sutra 2.5.0 for iOS.
- [Sutra Homepage](https://sutra-reader.com/): Visual feature overview, cross-platform app store links, and pricing parameters.
- [Help and FAQ](https://sutra-reader.com/help.html): Step-by-step local port configurations, remote connection diagnostics, and Tailscale/MagicDNS troubleshooting.
- [Privacy Policy](https://sutra-reader.com/privacy.html): Comprehensive zero-data-collection telemetry and storage details.
- [Changelog](https://sutra-reader.com/changelog.html): Version release logs mapping Material 3 updates, Swift/Kotlin refactors, and engine speedups.

## Reading and Library Guides

- [Kavita Reader Integration](https://sutra-reader.com/kavita-reader.html): Syncing progress via private API keys and personal OPDS endpoints.
- [Komga Reader Integration](https://sutra-reader.com/komga-reader.html): Pro requirements, bare server addresses, and activating Komga user Page Streaming permissions.
- [Comic Panel Reader Mode](https://sutra-reader.com/comic-panel-reader.html): How panel layout detection handles margin variance, black gutters, and staggered manga grids.
- [OPDS Reader Reference](https://sutra-reader.com/opds-reader.html): Generic feed formats, basic authentication, and download-to-device rules.
- [Calibre Family Reader Setup](https://sutra-reader.com/calibre-reader.html): Launching local Content Servers, authenticating reverse proxies, and allowing OPDS routes.
- [DRM-Free Ebook Sources](https://sutra-reader.com/drm-free.html): Hand-picked index of legal, independent digital book publishers and storefronts.

## Community and Feedback

- [Sutra Newsletter](https://newsletter.sutra-reader.com/): Development roadmap bulletins and feature announcements.
- [Feedback Portal](https://sutra-reader.com/feedback.html): Bug reporting channels and user feature request forms.