DuoRead — Support
Need help with DuoRead? We're happy to help.
Contact
Email support@sakura5.app — a real person reads it, usually replying within a couple of days. Tell us your device model and OS version and we'll get to the bottom of it faster.
What DuoRead does
DuoRead is the first reader dedicated to iPhone Duo. Folded, the outer screen shows the book you're reading as a closed book with its cover; unfolded, it opens to two facing pages with a physics page turn. It reads EPUB, PDF, DRM-free MOBI and AZW3, and DOCX, with highlights and notes, and DuoRead Premium adds AI Explain, Translate and Summarize. The app is available in English, Korean, Japanese and Spanish. No account is needed.
Frequently asked
- Which formats does DuoRead open? EPUB, PDF, MOBI, AZW3 (KF8) and DOCX — DRM-free files only.
- A book won't open. It is most likely protected by DRM, which includes most books bought in the Kindle Store. DuoRead tells you so on import and never removes or bypasses DRM. If a DRM-free file still fails, email us the format and your device model.
- Do I need an iPhone Duo? The closed-book cover and the two-page spread are made for iPhone Duo. On iPad in landscape and in a wide Mac window the reader also shows two facing pages; in iPad portrait and on any other iPhone it is a single-page reader.
- What is free, and what needs Premium? Every new install gets 3 days of everything free. After that, free means the complete reader, highlights, notes and dictionary for up to 3 books; DuoRead Premium adds the AI study tools (100 requests a day) and an unlimited library.
- How much is Premium? $5.99 a week, $15.99 a month, or $69.99 a year with a 3-day free trial on the yearly plan. It renews automatically until you cancel in iPhone Settings → your name → Subscriptions.
- I subscribed but Premium is locked, or I have a new device. Open the paywall and tap Restore Purchases while signed in with the Apple ID you subscribed with.
- Refunds. Payments go through Apple, so refunds are requested at reportaproblem.apple.com. Email us if something didn't work and we'll help.
- Where are my books stored? On your device, in the app's own storage. Deleting the app deletes the library it held, so keep your own copies of your files.
- What does an AI action send? With on-device Apple Intelligence, nothing. Otherwise only the text you selected, plus the target language or a short piece of context, goes through our Google Cloud server to Google Gemini to produce the answer, with a random install ID used only to count the 100 requests a day. We do not store the text or use it for training. See the privacy policy.
Common questions
- Restore a purchase: open the app's paywall and tap “Restore Purchases”.
- Manage a subscription: iPhone Settings → your name → Subscriptions.
- Bug or feedback: email us with your device model and iOS version.
DuoRead will be on the App Store soon.
Frequently asked questions
What does DuoRead do on iPhone Duo?
Folded, the outer screen shows the book you're reading as a closed book: its cover, full screen. Unfold it and the book opens to two facing pages, with the hinge as the spine and a physics page turn that follows your finger.
Which file formats does DuoRead open?
EPUB, PDF, MOBI, AZW3 and DOCX — DRM-free files only. Books protected by DRM, including most books bought in the Kindle Store, cannot be opened; DuoRead tells you so on import and never removes or bypasses DRM.
How much does DuoRead cost?
DuoRead is free to download and every new install gets 3 days of all features; after that the free tier gives you the complete reader with highlights and notes for up to 3 books. DuoRead Premium is a subscription at $5.99 a week, $15.99 a month, or $69.99 a year with a 3-day free trial on the yearly plan; it adds AI Explain, Translate and Summarize (100 requests a day) and an unlimited library.
Do my books leave my device?
No. There is no account, and your library, highlights and notes stay on your device. Only when you use a cloud AI feature is the selected text (with the target language or a short piece of context) sent to our Google Cloud server, which forwards it to Google Gemini to produce the answer, together with a random install ID used only to count the daily limit. We do not store the text or use it for training. With on-device Apple Intelligence, nothing is sent.
Which languages is DuoRead available in?
The app is available in English, Korean, Japanese and Spanish.
Who makes DuoRead?
DuoRead is made by Sakura5, an independent app studio that builds focused, privacy-first apps for iPhone, iPad and Mac. Support: support@sakura5.app.