Readest is an open-source, cross-platform ebook reader built with Next.js 16 and Tauri v2 for readers who want one modern library across macOS, Windows, Linux, Android, iOS, and the web.

What it is

Readest is an AGPL-3.0 licensed TypeScript application that serves as a modern rewrite of Foliate. It pairs Next.js 16 for the interface with Tauri v2 for native packaging, which lets a single codebase ship as a desktop app, a mobile app, and a web app rather than as separate platform builds. It lives in the Tauri and Next.js ecosystem, and its topic list places it alongside Calibre, KOReader, EPUB, MOBI, and OPDS tooling.

The concrete problem it replaces is reading spread across disconnected apps: a Foliate-style desktop reader on one machine, a phone reader elsewhere, and no shared progress. Readest adds cross-platform sync of book files, reading progress, notes, and bookmarks, library management, and OPDS/Calibre catalog access. Where Foliate targeted Linux desktops first, Readest targets all six platforms at once, which is the gap it fills.

Key capabilities

• Reads EPUB, PDF, MOBI, KF8 (AZW3), FB2, CBZ, TXT, and Markdown files, with scroll or paginated view modes.
• Syncs book files, reading progress, notes, and bookmarks across platforms, and syncs progress, notes, and bookmarks with KOReader devices.
• Integrates OPDS and Calibre to pull in online libraries and catalogs.
• Plays audiobooks and reads embedded EPUB 3 Media Overlays with timed highlighting, or pairs a reflowable EPUB with local DRM-free MP3, M4A, or M4B narration; Storyteller remains an option for phrase-aligned EPUBs.
• Offers dictionary and Wikipedia lookup, including importing local packs such as Yomitan ZIP and RDICT formats from Settings → Custom Dictionaries.
• Supports translation with DeepL and Yandex, multilingual text-to-speech, full-text search inside a book or across the current shelf, and parallel read in a split-screen view.
• Provides accessibility through full keyboard navigation and screen readers including VoiceOver, TalkBack, NVDA, and Orca, plus reading ruler, paragraph-by-paragraph mode, and speed reading aids.

Who uses it and how

• Readers who own several devices keep one library and one reading position instead of reconciling separate apps by hand.
• KOReader users keep progress, notes, and bookmarks in step with their dedicated e-ink devices.
• Language learners and students lean on dictionary packs, DeepL and Yandex translation, and TTS narration inside the same reading view.
• Users with accessibility needs rely on keyboard-only navigation and screen reader support across desktop and mobile.
• People with existing Calibre or OPDS catalogs connect those sources rather than rebuilding a library.

Getting started

The README points to a hosted web app at readest.com and to native downloads for each platform, with a Getting Started section in the documentation covering installation.

How it compares

Among the tools named in its own facts, Readest sits above Foliate as a cross-platform rewrite that keeps the same reading focus while adding sync, mobile, and web targets, and it sits beside KOReader by interoperating with it for progress sync rather than competing for the same devices. Calibre and OPDS support make it a reader for libraries people already maintain, not a replacement for the catalog itself.

When to use it — and when not to

Pick Readest if you want one reader across desktop, mobile, and web with sync and Calibre or OPDS integration. Do not pick it if you need a reader that is fully documented for self-hosted deployment: the provided README excerpt describes sync and catalogs but does not spell out the backend, storage, or account services a self-hoster would operate, and several items still sit under Planned or Building rather than shipped. The repository also carries a substantial open issue count and an AGPL-3.0 licence, which matters if you intend to embed it in proprietary work.

nix run --accept-flake-config github:readest/readest

# Due to a limitation in how Nix fetches submodules, a regular GitHub input type will fail to evaluate.
inputs.readest = {
  url = "https://github.com/readest/readest.git";
  type = "git";
  submodules = true;
};