Android · EPUB · Private Sync

Private EPUB reader with resilient sync and AI-linked notes.

Fast on e-ink, with Supabase Postgres/Storage mirroring your books, progress, and bookmarks. Improved i18n keeps the UI consistent across languages, and AI responses stay tethered to the passages you highlight.

Get latest APK on GitHub View source on GitHub
Private sync (per-user Supabase) Full EPUB backup to Cloudflare R2 Optimized for Boox & Android Better language support (i18n)
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Cloud Sync

Progress, bookmarks, AI notes, and book files are backed up to your account.

Cloudflare R2
Supabase Postgres

Why readers switch

Fast, focused reading with resilient sync.

Everything you mark—notes, bookmarks, and progress—stays with the book, wherever you read.

Full book backup

EPUBs upload with checksum validation, keeping your library safe and deduplicated across devices.

Progress & bookmarks

Per-page progress and bookmarks mirror through Supabase. Open on any device and continue exactly where you left off.

AI-linked notes

Generate AI explanations tied to passages. Notes stay searchable by book, keyword, and your custom AI profiles.

E-ink tuned

Reduced motion, adjustable font weight/size, and Boox-specific refresh controls to keep pages crisp on e-ink.

Language-friendly UI

Improved i18n with clearer translations, better formatting, and safer fallback behavior across locales.

Secure by default

Row-level security policies, upload-size guards, and SHA-256 checks. Local data stays private to your account.

Open & portable

Runs on standard EPUB; no vendor lock-in. Export notes, and configure your own backend URLs if needed.

How it works

Resilient sync pipeline

  • Book files: On first open, the EPUB uploads to Cloudflare R2 with checksum metadata; repeated opens reuse the stored copy if unchanged.
  • Progress: Locator JSON cached locally and mirrored to Supabase for instant resume on any device.
  • Bookmarks & notes: Stored locally for offline, then pushed to Supabase; pulls on demand to keep devices aligned.

Privacy stance

Your library and notes are scoped to your account. No sharing or public listings—just your data on your devices.

Per-user rules Checksum uploads Offline-first

Get started

Install and sync in minutes

  1. Install the latest APK from GitHub Releases.
  2. Sign in with your account to enable Supabase sync.
  3. Open an EPUB and start reading—your progress and files back up automatically.