Privacy Policy

App: BookHoard  ·  Effective: April 2026  ·  Contact: support@bookhoardapp.com

Short version: BookHoard does not sell your data, does not use your data for advertising, and does not share your reading information with third parties beyond what is strictly necessary to operate the app. Your library is yours.

1. Who we are

BookHoard is a personal library app. This policy explains what data we collect, why we collect it, and how it is used and protected.

If you have questions or requests about your data, contact us at support@bookhoardapp.com.

2. Data we collect and why

Account information

When you create a BookHoard account, we collect your email address. This is used solely to authenticate your account, send you password-reset emails, and deliver essential transactional messages. We do not use your email address for marketing.

Library data

BookHoard stores the library data you choose to add: book titles, authors, ratings, personal notes, tags, reading format (physical, digital, audiobook, or borrowed), location tags, and — for borrowed books — an optional due-back date. This data is synced to a secure cloud database so you can access your library across devices. It is never shared with third parties, never used for advertising, and never sold.

Genre preferences

During onboarding, you may select genre preferences. These preferences are stored with your account and used only to improve your in-app recommendations.

Camera

BookHoard uses your device camera for three purposes: scanning ISBN barcodes, reading ISBN text via OCR (optical character recognition), and scanning bookshelf photos. Images captured during these scans are never stored on our servers.

ISBN text recognition is performed entirely on your device using built-in platform technology (Apple Vision on iOS, Google ML Kit on Android). These images are never transmitted to Apple, Google, or our servers — only the extracted ISBN text is used to look up book information.

Shelf photos are passed directly to our spine-recognition provider (Google Gemini — see Section 3) for processing and are immediately discarded. They are never stored on BookHoard's servers.

Approximate location

The bookstore finder feature uses your device's approximate location to show nearby independent bookstores. Location access is requested only when you use this feature. Your location is never stored and never shared — it is used in real time to query a map service, then discarded.

Purchase and subscription data

If you subscribe to Hoard+, purchase validation data (receipt information) is handled by our subscription provider, RevenueCat. This data is used solely to confirm your subscription status. It is not used for advertising and is not sold.

Crash and error data

We collect crash reports and error logs to help us fix bugs and improve stability. These reports may include your account identifier so we can investigate crashes affecting a specific user. They do not include reading data, book titles, ratings, notes, tags, or other library content. See Section 3 for details on our crash monitoring provider.

Usage analytics

BookHoard captures aggregate product-usage events to help us understand which features are used and where onboarding drops off. Examples of recorded events include "book added," "scan completed," and "paywall viewed." Events are tied to your account identifier so we can measure how features perform per user, but we do not capture the content of your library (titles, ratings, notes, tags). See Section 3 for details on our analytics provider.

3. Third-party services (vendors)

BookHoard uses the following third-party services to operate. Each vendor is listed with a description of what data they receive and why.

Supabase — Database & Authentication

Supabase stores your account information (email address) and your library data. All data is stored in a secure, access-controlled database. Supabase acts as our data processor and does not use your data for any purpose other than providing database services to BookHoard. → supabase.com/privacy

Anthropic — Recommendation Engine

BookHoard uses Anthropic's Claude model to power two features: personalised reading recommendations on the For You tab, and "Find Similar Books" from a book's detail page. For recommendations, we send anonymised library patterns — genre breakdown, rating distributions, and tag patterns. For "Find Similar Books", the title of the book you are viewing is sent. We never send personal notes, your email address, or any other personally identifiable information to Anthropic. Data sent to Anthropic is used only to generate your response and is not used to train AI models. → anthropic.com/privacy

Google Gemini — Shelf Scan

BookHoard uses Google's Gemini model to identify books from a photograph of your bookshelf. When you tap "Scan shelf" and take a photo, the image is transmitted to Gemini for spine recognition. The image is processed in real time and is not stored by BookHoard. Google's API terms specify that data sent through the Gemini API is not used to train Google's models. No account information, library data, or personally identifiable information is sent alongside the image. → ai.google.dev/gemini-api/terms

Google Places API — Bookstore Finder

When you use the bookstore finder, your approximate location is sent to the Google Places API to return nearby bookstore results. Google receives only the location coordinates — no account information, no library data. Location data is not stored by BookHoard after the query completes. → policies.google.com/privacy

Resend — Transactional Email

Resend delivers transactional emails on our behalf, including password-reset emails and authentication messages. Resend receives your email address solely for the purpose of delivering these messages. → resend.com/privacy

Sentry — Crash Monitoring

We use Sentry to monitor app stability. Error reports may include your account identifier so we can investigate crashes affecting a specific user. Reports do not include reading history, book titles, ratings, notes, tags, or other library content. We do not use Sentry's Session Replay feature. Error data is retained for 30 days. → sentry.io/privacy

PostHog — Product Analytics

We use PostHog to understand how BookHoard is used in aggregate — which features people use, where onboarding drops off, how often the scanner is opened. Events captured include actions like "book added," "scan completed," and "paywall viewed." Each event is tied to your account identifier so we can measure feature adoption and improve the app. We do not capture book titles, ratings, notes, tags, or other library content. PostHog is configured with autocapture disabled — only the events we explicitly track are recorded. Analytics data is retained for 12 months. → posthog.com/privacy

Cloudflare R2 — Encrypted Database Backups

BookHoard's database is backed up weekly to Cloudflare R2 (Cloudflare's object storage). Backups contain all account and library data, encrypted at rest. Backups exist only as a disaster-recovery measure — they are never accessed for any other purpose, are not shared with any third party, and old backups are automatically deleted after eight weeks. → cloudflare.com/privacypolicy

RevenueCat — Subscription Management

We use RevenueCat to manage subscriptions. RevenueCat may collect purchase history solely for receipt validation and subscription management. This data is not used for advertising and is not sold. → revenuecat.com/privacy

Apple Vision & Google ML Kit — On-Device Text Recognition

BookHoard uses built-in platform OCR technology to read ISBN text from book covers: Apple Vision Framework on iOS and Google ML Kit on Android. All text recognition happens entirely on your device. No images or extracted text are sent to Apple or Google — the processing is local and offline-capable. Only the ISBN number identified by the OCR is used by BookHoard to look up book information.

ISBNdb — Book Metadata

BookHoard uses ISBNdb to look up book metadata (title, author, publisher, cover image, description, and subject classification) in three situations: when you scan a barcode, when you use "Look up missing details", and automatically in the background the first time you open a book's detail page. ISBNdb receives the book's ISBN or title — no account information or personal data is sent. Each book is looked up at most once; results are stored in your library permanently. → isbndb.com/privacy-policy

Open Library — Book Search, Covers & Metadata

BookHoard uses Open Library (a project of the Internet Archive) for real-time book search, cover images, and as a metadata fallback when ISBNdb does not have complete information for a book. Open Library also provides cover images for the Banned Books list. Open Library receives book titles, author names, and ISBNs — no account information or personal data is sent. Open Library data is available under a Creative Commons license. → openlibrary.org/about

Library of Congress — Book Metadata (fallback)

For books where neither ISBNdb nor Open Library has complete metadata — particularly older or out-of-print titles — BookHoard queries the Library of Congress catalogue as a last resort to fill in missing details such as description, publisher, or publication year. The Library of Congress receives book titles and author names. No cover images are retrieved from this source, and no account information or personal data is sent. → loc.gov/legal

OpenStreetMap / Overpass API — Little Free Libraries

When you use the "Find nearby" feature, your approximate location coordinates are sent to the Overpass API (a service that queries OpenStreetMap data) to find Little Free Libraries near you. The same location data is also sent to Google Places API (see above) for bookstores and libraries. Location data is not stored by BookHoard after the query completes. Map data © OpenStreetMap contributors, available under the Open Database Licence. → openstreetmap.org/copyright

The New York Times Books API — Bestseller Lists

BookHoard displays NYT Bestseller Lists in the Discover tab. To load these lists, requests are sent to the NYT Books API — no personal data or account information is included in these requests. Bestseller data is provided by The New York Times. → developer.nytimes.com

Affiliate Links — Bookshop.org, Amazon, Audible & eBay

When you tap a "Buy" link in the app or on a shared wishlist page, some of those links include affiliate tracking parameters. BookHoard participates in the Bookshop.org Affiliate Program, the Amazon Associates Program, and the eBay Partner Network. If you purchase through these links, BookHoard may earn a small commission at no extra cost to you. No personal data is shared with these retailers through the affiliate links — only a tag identifying BookHoard as the referral source. → bookshop.org · Amazon Associates

4. Data we do not collect

  • We do not collect or store shelf photos or barcode scan images.
  • We do not track your location persistently or store it.
  • We do not embed any advertising SDKs or third-party tracking libraries.
  • We do not build advertising profiles or share data with ad networks.
  • We do not sell your data — ever.

5. Data retention

Your account and library data are retained for as long as you have an active account. Crash and error data collected by Sentry is retained for 30 days. If you delete your account, your library data and account information are deleted from our systems.

6. Your rights and choices

You have the right to:

  • Access the personal data we hold about you.
  • Correct inaccurate data.
  • Delete your account and all associated data.
  • Export your library data (available in the app).

You can delete your account directly in the app via Settings → Account → Delete Account. This will permanently delete your library data and account information. For any other data requests, contact us at support@bookhoardapp.com.

7. Children's privacy

BookHoard 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 and we will delete it promptly.

8. Changes to this policy

If we make material changes to this privacy policy, we will update the effective date at the top of this page and, where appropriate, notify you within the app. Continued use of BookHoard after changes take effect constitutes acceptance of the updated policy.

9. Contact

Questions, concerns, or data requests — please email us at support@bookhoardapp.com. We aim to respond within 5 business days.