CaliMob FAQ — Calibre on Android & iOS, Formats, Cloud Sync

What is CaliMob?

CaliMob is a mobile ebook reader for Android and iOS that connects to your Calibre library. Read EPUB, PDF, comics, and audiobooks on your phone or tablet — synced from Google Drive, OneDrive, Dropbox, WebDAV, or any of 8 cloud backends. Think of it as your Calibre library in your pocket.

Is CaliMob free?

Yes! CaliMob is free to download and use. A premium plan is available for advanced features like multi-library sync and cloud storage.

Which formats does CaliMob support?

CaliMob reads EPUB, PDF, MOBI, AZW3, CBZ, CBR (comics), and plays audiobooks (MP3, M4B, OGG, FLAC). It supports customizable fonts, themes, day/night modes, and text-to-speech.

How do I add books to CaliMob?

CaliMob supports 8 ways to add books:

• Google Drive — point to your Calibre library folder on Drive
• OneDrive — point to your Calibre library folder on OneDrive
• Dropbox — automatic sync with your Dropbox folder
• WebDAV / Nextcloud — self-hosted, privacy-first
• FTP / SFTP — connect to any network storage
• OPDS catalogs — browse and download from online libraries
• Calibre Content Server — direct connection to Calibre on your computer
• Local storage / SD card — import files directly from your device

What is the Demo Library?

CaliMob includes a Demo Library with free public domain ebooks, comics (Pepper&Carrot), and sample audiobooks. It’s a great way to explore all features without setting up your own library first. The demo content is accessible via OPDS from the app.

Do I need a Calibre library to use CaliMob?

No. You can import books from local storage, SD card, or OPDS catalogs without having Calibre. But CaliMob shines when connected to your Calibre library — it syncs all your metadata, covers, series, and tags automatically.

I picked a file but no book appeared — what happened?

This used to happen in complete silence, which made it hard to even report. Two things have changed. First, the app now tells you when an import didn’t work, instead of returning you to an unchanged library with no explanation.

Second, the most common cause is fixed. On iPhone and iPad, reinstalling or updating an app can make iOS hand it a new private storage area and quietly retire the old one. CaliMob used to remember the old location and try to file incoming books into a folder that no longer existed. It now detects the move and corrects itself the next time you open it — nothing for you to do, and no books are lost.

If you still get an import error, the usual causes are ordinary: a file the app doesn’t recognise as a book, a half-finished download, or a file still syncing from iCloud Drive and not yet really on the device. Wait for it to finish downloading, or try another file.

Can I read comics and manga?

Yes. CaliMob has a dedicated comic reader for CBZ and CBR files with double-page mode, manga right-to-left reading, and panel-by-panel navigation.

Does CaliMob support audiobooks?

Yes. The built-in audiobook player supports chapter navigation, playback speed control (0.5×–3×), sleep timer, and background playback. Supported formats: MP3, M4B, OGG, FLAC.

Can I customize my reading experience?

Absolutely. CaliMob offers day, night, and sepia themes (or create your own), customizable fonts and margins, adjustable brightness, text-to-speech, and bookmarks. Your reading position syncs across devices.

I pressed Translate and my text came back unchanged — why?

That shouldn't happen any more. The plain Translate in the reader is the quick machine kind — free, no AI opt-in needed. When the translation service can't be reached, the reader now says so ("translation service is currently unavailable") rather than quietly returning your own words as if they had been translated. If you see that message, try again in a moment; if you want a translation that reads like prose, use the AI Translate in the same menu, which uses your AI credits.

Does CaliMob work offline?

Yes. Once books are downloaded to your device, you can read them without an internet connection. Metadata and covers sync when you’re online; reading is fully offline.

Does CaliMob track my reading habits?

No. All data stays on your device. CaliMob does not collect analytics on what you read, when you read, or how much you read. Your library, your data, your control.

What is CaliWeb?

CaliWeb is the browser companion to CaliMob. You can try a live preview with no account. Full cloud backup of your own library and cross-device sync are optional paid CaliWeb features that require an account. CaliMob works fully without CaliWeb when you use your own cloud storage (Google Drive, WebDAV, etc.).

Does this website track what I read?

No. caliwebapp.com may use cookie-based analytics (such as Google Analytics) only with your consent — see our Cookie Policy. That applies to this marketing site, not to CaliMob the app, which does not collect reading analytics.

Is CaliMob available on iOS (iPhone/iPad)?

Yes — CaliMob is available on both Google Play (Android) and the App Store (iPhone & iPad).

How do I sync my Calibre library to my phone?

Upload your Calibre library folder to Google Drive, OneDrive, Dropbox, or a WebDAV server. In CaliMob, tap “Add Library”, choose your cloud backend, and point to the folder. CaliMob reads the Calibre metadata.db and syncs all your books, covers, series, and tags automatically.

What is the Calibre plugin for CaliMob?

The CaliMob plugin for Calibre will enable bidirectional sync between your desktop Calibre library and CaliMob, pushing metadata, covers and reading progress in both directions without needing a cloud folder. It is not published yet, so you will not find it in Calibre’s plugin manager: today you sync through a cloud folder, Calibre’s content server or a Wireless Device connection.

Does CaliMob support highlights and annotations?

Yes. You can highlight text, add notes, and create bookmarks in EPUB and PDF files. Annotations sync across devices via CaliWeb backup, so your highlights are never lost.

Can I manage multiple Calibre libraries?

Yes. CaliMob supports multiple libraries from different cloud backends simultaneously. Switch between your fiction, non-fiction, and comics libraries from the drawer menu. Multi-library sync is available with the premium plan.

How does CaliMob compare to Moon+ Reader?

Moon+ Reader is a standalone ebook reader. CaliMob is designed specifically for Calibre users — it syncs your existing Calibre library metadata, covers, series, and tags via 8 cloud backends. If you use Calibre to manage your books, CaliMob is the only mobile app that connects directly to your library structure.

What is the difference between CaliMob and ReadEra?

ReadEra is a local-only reader with no cloud sync to Calibre. CaliMob syncs your Calibre library from Google Drive, OneDrive, Dropbox, WebDAV, FTP, or OPDS. ReadEra supports more niche formats (DJVU, FB2, CHM); CaliMob focuses on the formats Calibre manages (EPUB, PDF, CBR/CBZ, MOBI, audiobooks) and adds a dedicated comic reader with manga mode.

CaliMob vs Calibre Companion — what is the difference?

Calibre Companion (Android) connects as a Wireless Device, browses Content Server/OPDS, and can use cloud folders (Dropbox, OneDrive, Google Drive, Box, and more) — but it has no built-in reader. CaliMob is a full EPUB/PDF/comics/audiobook reader on Android and iOS, with backends including Google Drive, OneDrive, Dropbox, WebDAV, FTP/SFTP, OPDS, Content Server, and Wireless Device Connect/Share (WebDAV and FTP/SFTP are Companion gaps). Optional Calibre plugin / CaliWeb sync is available.

Can I connect my library to an AI assistant like Claude?

Yes, on a Pro plan or higher. CaliMob exposes an MCP (Model Context Protocol) server: connect your library to Claude Desktop or any MCP client and the assistant gets read-only access to your books, reading history and progress for personalised, spoiler-free answers. Generate the token from Profile → API Settings. Your data stays private (read-only, per-user). See the setup guide.

Why can’t I download a book from CaliWeb?

If a book shows as unavailable, your library has probably grown past your current plan’s limit — a subscription lapsed or you downgraded — so CaliWeb has paused the backup for the newest overspill. Nothing is deleted: the book, cover and details are still there. Only books whose sole copy is CaliWeb itself stop downloading; books from your own source (Dropbox, a drive, your device) keep opening as normal. Re-subscribing to a plan that fits makes them downloadable again automatically.

My library says “backup paused” — what does that mean?

When your library goes above your plan’s limit, CaliWeb pauses the backup for the newest books it can’t fit instead of deleting anything. Those books still appear in your library, and if they live in your own source you keep reading and adding to them — only the CaliWeb copy is on hold. Freezing always starts with your most recent additions, so older, established libraries keep backing up. Your highlights and notes are never affected. Re-subscribe to lift the pause.

I re-subscribed — will my books come back?

Yes, automatically, with nothing to click. Moving back to a plan that fits your library re-activates everything that was paused, up to the new plan’s limits: backups resume and any CaliWeb-only books become downloadable again. Because your content was only ever paused, never deleted, there’s nothing to restore by hand. And you can always export a library’s details (CSV or JSON) from the website meanwhile, so your data is never out of reach.