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CalibReader: EPUB & PDF Reader icon
Built for Duo

CalibReader: EPUB & PDF Reader

Read DRM-free EPUB and PDF files from folders or a calibre library, with reading positions synced between devices.

Gram 1 · Reading & News · Free

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iPhone screenshots

CalibReader: EPUB & PDF Reader — iPhone screenshots 1
CalibReader: EPUB & PDF Reader — iPhone screenshots 2

How it uses iPhone Duo

Opening Duo shows a two-page spread; closing presents the book cover on the outer screen, where a tap resumes one-page reading. Open portrait uses one page and reading position survives folding.

What’s New

Version 1.0.2 ·

• A redesigned app icon: an open book, with Dark, Clear and Tinted versions. • Margins can now go all the way to zero, and Reset Margins puts them back. • Floating reading controls are frosted, so they stay readable over text. • Dropbox and iCloud libraries load faster, and switching libraries is safe and calm, with one status line at the top. • Plain folders of ebooks now open from your NAS, Dropbox, iCloud Drive and OneDrive, even without a calibre library. • OneDrive sign-in and folder browsing are more reliable. • Covers for more books, including series titles. • iPad in landscape opens books as a two-page spread, iPad mini included. • On two-page spreads, tap the middle for the controls and the edges to turn the page. • A sample library of 8 classics to try the app without your own books. • Fixes for iPhone Duo, dark mode and labels.

App Store descriptionWritten by the developer.

Read your EPUBs like a real book: two pages side by side on iPad and iPhone Duo, with real page curls. PDFs open as two-page spreads too. Open your ebook files straight from Files, Safari, Mail or AirDrop, or bring your whole calibre library: CalibReader shelves them with covers and series, and keeps your place on every device. BUILT FOR IPHONE DUO Open iPhone Duo and your book becomes a two-page spread, with real page curls. Close it and the book closes: the cover screen shows its cover, leather-bound with the title in gold or the original art. Tap to keep reading, one page at a time. Your place holds through every fold, and turning the open phone to portrait gives you a single page. YOUR EPUB AND PDF FILES Any folder of EPUB or PDF files becomes a library with covers, sorting and search. WORKS WITH YOUR CALIBRE LIBRARY Point CalibReader at your calibre library folder and every book, cover, series, tag and synopsis appears as you organised it. Nothing to convert, no lock-in. YOUR STORAGE, YOUR CHOICE • A folder on your device or in iCloud Drive • Dropbox and OneDrive • Your own server or NAS over SMB • Other apps that share a folder in Files A READER BUILT FOR LONG SESSIONS • Two-page spread, single page or continuous scroll, with page curl or flip • Opens on a title page that turns over like a real one • Parchment, sepia, black and navy themes, or your own colour • Font, size, spacing, margins and justification, applied live • Table of contents, chapter navigation, clock and progress footer • Built-in dictionary • A PDF reader with two-page spreads on iPad and iPhone Duo that remembers your page PICK UP WHERE YOU LEFT OFF Reading positions and read status sync across your devices through a tiny file in your library folder. Put down the iPad, pick up the iPhone. A free calibre plugin writes read status, % read and last-read date back to your desktop library. A LIBRARY THAT LOOKS LIKE A LIBRARY Home with continue reading and recently added; grid, list and series views; filters and search; cover art found automatically when a book has none, and Choose Cover to swap in another edition's cover or bind any book in leather. 3 BOOKS FREE, THEN ONE PURCHASE Read any 3 books free, and bring in, sync and browse as many as you like. Then unlock your whole library with one purchase. No subscription, no account, no ads, no tracking, and no data collected. Formats: EPUB and PDF in the built-in reader; other formats open in the app of your choice. Note: CalibReader opens EPUB and PDF files without copy protection (DRM). Books bought in other apps' stores stay in those apps. CalibReader is an independent app, not affiliated with or endorsed by the calibre project. calibre is a trademark of Kovid Goyal. Support: hello@calibreader.com · https://calibreader.com

CalibReader: EPUB & PDF Reader on iPhone Duo: FAQ

Is CalibReader: EPUB & PDF Reader optimized for iPhone Duo?

Yes. CalibReader: EPUB & PDF Reader is Built for Duo: it uses the fold, Split View or the outer display. Verified on October 31, 2026 (Developer statement).

What does CalibReader: EPUB & PDF Reader look like on iPhone Duo?

Opening Duo shows a two-page spread; closing presents the book cover on the outer screen, where a tap resumes one-page reading. Open portrait uses one page and reading position survives folding.

How much does CalibReader: EPUB & PDF Reader cost?

CalibReader: EPUB & PDF Reader is free to download on the App Store.

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