Privacy Policy

ShelfControl — Last updated: July 9, 2026

ShelfControl ("the app") is a personal book library app. This policy explains what data is collected, how it is used, and your rights regarding that data.

1. Data We Collect

• Account information: email address and a display name, used to identify your account.
• Library data: books you add (title, author, ISBN, genre, format), reading status, and reading dates.
• Shared library data: if you join or create a shared library, other members of that library can see the books and reading statuses you add to it.
• Error reports: if the app encounters an unexpected error, a diagnostic report is sent to our error-monitoring provider (Sentry) to help fix the issue. Reports contain technical details about the error and an identifier for your account, but not your book data.

2. How We Use Your Data

• To provide the app's core features: storing and syncing your library across devices.
• To enable shared libraries: syncing data between members of the same library in real time.
• To fix bugs: error reports are used solely for diagnosing and resolving technical issues.

We do not sell your data, use it for advertising, or share it with third parties beyond what is described in this policy.

3. Third-Party Services

• Supabase — cloud database and authentication provider. Your data is stored on Supabase-managed infrastructure. See supabase.com/privacy.
• Google Books API — used to look up book metadata by ISBN or title. Queries may include ISBNs or search terms you type. See Google's privacy policy.
• Open Library (Internet Archive) — used as a fallback for book metadata when Google Books returns no result. See archive.org/about/terms.
• Sentry — error-monitoring service that receives crash and error reports, tagged with an identifier for your account so issues can be diagnosed. Book data is not included. See sentry.io/privacy.

4. Data Storage

Your library is stored locally on your device (SQLite) and synced to Supabase cloud storage. Local data persists until you sign out or uninstall the app. Cloud data is retained as long as your account exists.

5. Deleting Your Data

You can remove individual books or shared libraries from within the app at any time.

Delete your account: in the app, go to Profile → Delete my account. This permanently deletes your account and associated personal data (profile, reading history and dates, and library memberships). If you are the sole member of a library, that library is deleted with it; shared libraries you belong to remain for their other members. Corrections you made to shared book details (see section 6) stay part of the shared catalogue and are no longer linked to you. This action is immediate and cannot be undone.

Alternatively, to request deletion by email, contact for.shelf.control@gmail.com with the subject line "Data Deletion Request" and the email address linked to your account. We will action email requests as soon as possible, and at the latest within 30 days.

6. Shared Book Data & Corrections

Book metadata (title, author, series, genres, etc.) is shared across everyone using Shelf Control rather than stored per user. Any signed-in user can suggest corrections to this shared data; the value with the most agreement becomes the one shown to everyone. Designated admins can make authoritative edits and lock individual fields to protect verified data. Your suggested edits are associated with your account. To request admin access, email for.shelf.control@gmail.com.

7. Children

ShelfControl is not directed at children under 13. We do not knowingly collect data from children under 13.

8. Changes to This Policy

If this policy changes materially, the updated version will be posted here with a revised date. Continued use of the app after changes constitutes acceptance of the updated policy.

9. Contact

Questions or requests: for.shelf.control@gmail.com