Byblos is a personal book cataloguing app. We collect only what we need to make the app work, and we never sell your data.
What we collect
When you use Byblos, we may collect:
- Account information — your email address and a display name when you sign up via email, Apple Sign-In, or Google Sign-In.
- Library data — the books you add, your reading statuses, ratings, reviews, and collections. This is stored in your personal account.
- Camera images — photos you take of your bookshelf are sent to our server to identify books. We do not store these images after processing.
- Usage analytics — basic analytics about which features you use, to help us improve the app. This data is anonymised and not linked to your identity.
- Crash reports — if the app crashes, an error report is sent to help us fix bugs. These reports do not include your library data.
How we use your data
- To sync your library across your devices
- To identify books from shelf photos using AI
- To generate personalised book recommendations
- To calculate your reader personality and stats
- To enable social features (following, buddy reads, activity feed)
- To fix bugs and improve the app
Third-party services
Byblos uses the following third-party services, each with their own privacy policies:
- Firebase (Google) — account authentication and data storage. Privacy policy
- Anthropic (Claude) — AI-powered book recommendations and chat. Text queries are processed according to Anthropic's privacy policy.
- Google Gemini API — AI-powered book identification from shelf photos. Images are processed according to Google's terms.
- RevenueCat — in-app purchase and subscription management. Privacy policy
- Sentry — crash reporting and error tracking. Privacy policy
- PostHog — anonymised product analytics. Privacy policy
Camera and photo access
Byblos requests camera access to scan bookshelves and ISBN barcodes. Photos are sent to our server solely to identify books. We do not store, share, or use these images for any other purpose. You can add books manually without granting camera access.
Data sharing
We do not sell, rent, or trade your personal information to third parties. We do not display advertisements. Your library data is private by default — you choose what to share publicly via the social and sharing features.
Data retention and deletion
Your account and library data are retained as long as your account is active. You can delete your account and all associated data at any time from within the app (Profile → Privacy → Delete Account). Upon deletion, your data is permanently removed within 30 days.
Children's privacy
Byblos is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has provided us with personal information, please contact us so we can delete it.
Changes to this policy
We may update this policy as the app evolves. We will notify you of significant changes through the app. Continued use of Byblos after changes means you accept the updated policy.