Privacy Policy

1. Who is responsible

The controller for BookTamer is WEBGEHEUER OÜ, registry code 16922871, Estonian Business Register, Sepapaja 6, 15551 Tallinn, Estonia.

For privacy questions or requests, email hello@booktamer.app.

This policy covers the BookTamer website at booktamer.app and the BookTamer apps for iOS and Android.

2. The BookTamer website

Hosting and technical logs

Vercel hosts the website. When you open a page, Vercel processes the information needed to deliver and protect it. This can include your IP address, requested URL, request time, browser and device information, referrer, and security or diagnostic data. We use this information to provide the site, prevent abuse, and investigate technical problems. Our legal basis is our legitimate interest in operating a secure and reliable website.

Provider: Vercel Inc., United States. Read the Vercel Privacy Notice.

Web Analytics and preferences

The website uses Vercel Web Analytics to produce aggregated reports about page views, routes, referrers, country, browser, device, and operating system. Vercel states that this service does not use third-party cookies and stores anonymized analytics data. We use the reports for our legitimate interest in understanding and improving the website. Read Vercel's Web Analytics privacy information.

The website does not use Speed Insights, Google Analytics, advertising pixels, or the old WordPress analytics tags.

The website also saves two display preferences:

• booktamer-locale stores English or German in a cookie for one year. On your first visit, the website can initialize it from your browser's Accept-Language setting. A later language choice updates it. The cookie uses SameSite=Lax and Path=/.
• booktamer-theme stores your system, light, or dark appearance choice in local storage until you clear it.

These preferences are used only to provide the setting you selected. They are not used for advertising or cross-site tracking. You can remove them in your browser settings.

External and affiliate links

The website links to app stores, book-data providers, booksellers, and historical sources. BookTamer contacts a destination only after you choose its link. That provider then handles information under its own privacy policy.

Some links in the historical German archive are affiliate links. They are identified on the page and marked as sponsored. If you buy through one of those links, BookTamer may receive a commission. Active archive links go directly to their stated destinations.

3. Information stored by the app

Your library, reading lists, journal, ratings, comments, profile, custom images, and preferences are stored primarily on your device. BookTamer has no user account and does not sync your library to a BookTamer cloud database.

The manual backup is a readable JSON file. It can include your profile name and image, first-use date, TBR, finished books, titles, authors, ISBNs, covers, dates, ratings, and comments. It is a partial backup, not a complete data export. In particular, it does not include every preference or reading-list state. You choose where to save or share the file. If normal sharing fails, the app may leave a persistent .bak file in device storage.

Android, iOS, iCloud, computer, or other operating-system backups may keep copies according to your device and account settings. Files you export remain wherever you save or share them.

4. Book searches, ISBN lookups, and covers

When you search for a book or scan an ISBN, the app sends the search term or ISBN and selected language to ISBNdb or Google Books. Google Books can also complete missing details in an ISBNdb result. These providers receive the connection information needed to answer the request, such as your IP address. A remote cover host can also receive a request when the app displays that cover.

The app does not access private Google Books shelves or other Google account data.

• ISBNdb Privacy Policy
• Google Privacy Policy

5. Camera, photos, and on-device scanning

BookTamer requests camera access when you choose to scan a barcode or recognize ISBN text. It requests photo access when you select a profile image or custom book cover. You can change these permissions in your device settings.

Barcode and text recognition run on the device. The app can send the ISBN extracted from a scan to ISBNdb or Google Books, but it does not send scan image pixels or recognized text to those catalog providers.

The native scanner includes Google ML Kit. Google states that scan input and results stay on the device. The SDK may contact Google for models, fixes, compatibility checks, and diagnostics. Its disclosures list device and app information, a per-install identifier, API configuration, input and output sizes, event types, performance, and errors, but not image pixels or recognized text.

• ML Kit Android data disclosure
• ML Kit iOS data disclosure

6. App analytics

Native versions of BookTamer use Google Analytics for Firebase to understand app reliability and feature use. Firebase can process an app-instance identifier, sessions, approximate location, device and app information, and interactions with the app. BookTamer records events such as feature use, book-addition counts and destinations, premium-screen activity, offering and package identifiers, trial eligibility, confirmed access methods, selected churn reasons, and whether an optional feedback field was filled in. It does not include the text from that field. Firebase can also collect automatic purchase and subscription events with product, value, currency, subscription, and trial information, depending on the platform and Firebase configuration.

BookTamer does not add book titles, authors, ISBNs, journal notes, profile names, email addresses, payment details, receipts, transaction identifiers, or free-form feedback to its custom analytics events. Analytics is not used when BookTamer runs as a web app. Current native releases do not include an in-app analytics opt-out.

We use this information for our legitimate interest in improving and securing the app where that processing is permitted without consent. Google processes the information under our Firebase configuration and its own legal obligations. Read Firebase privacy and security information and the Google Privacy Policy.

7. Purchases and subscriptions

On native apps, RevenueCat checks Premium access, displays offers, supports purchases and restoration, and measures paywall presentation. BookTamer does not give RevenueCat a BookTamer account, name, email address, or phone number. RevenueCat creates an anonymous app user ID and can process product and offering IDs, entitlement and subscription status, purchase timing, store receipts or purchase tokens, transaction, device, and network information.

Apple App Store or Google Play processes the payment. BookTamer does not receive your full payment-card details. Read the RevenueCat Privacy Policy, Apple App Store privacy information, and Google Privacy Policy.

8. Support, feedback, and sharing

When you choose support, feedback, or error reporting, BookTamer opens your email app with a draft. Depending on the action, it can contain a failed search, optional churn feedback of up to 500 characters, or technical error and React component diagnostics. Nothing is sent until you choose to send the email. Your email provider and our support-mail provider process the message, headers, delivery information, and any attachment you add. Access is limited to people authorized to handle BookTamer support.

We normally keep support correspondence for up to 12 months after the request is resolved, unless we need it longer to establish, exercise, or defend legal claims or to meet a legal obligation.

App-store update checks, reviews, purchases, and restoration contact Apple App Store or Google Play. Sharing, Instagram, and other external destinations open only when you choose them.

9. Retention and deletion

Local app data stays until you remove it, clear app storage, or uninstall the app. Device backups, exported files, generated share images, and persistent backup files can survive and must be removed from their storage location separately. Service providers keep information according to our configuration, their contracts, and applicable legal obligations. We keep provider information only as long as needed for the purposes in this policy or to meet legal requirements.

Because BookTamer has no account or cloud library, we cannot delete a library stored only on your device. We can handle requests concerning support messages and, when you can provide a relevant app identifier, forward requests concerning provider records. Some anonymous records cannot be located from your name or email address alone.

10. International transfers

Some providers are based in or process information in the United States and other countries outside the European Economic Area. Where required, we and our providers use recognized safeguards such as European Commission standard contractual clauses. Provider privacy notices explain their locations and safeguards in more detail.

11. Your rights

Where the GDPR applies, you may have rights to information, access, correction, deletion, restriction, portability, and objection, subject to the conditions in the law. Where processing relies on consent, you may withdraw it for the future. BookTamer does not use personal data for automated decisions that produce legal or similarly significant effects.

Email hello@booktamer.app to make a request. You may also complain to the supervisory authority where you live, work, or believe an infringement occurred. You may also contact the Estonian Data Protection Inspectorate.

12. Children

BookTamer is a general-audience reading app and is not directed at children. If you do not have legal capacity to agree to the applicable terms or make a purchase, use the service only with permission from a parent or legal guardian. Contact us if you believe a child has provided personal data to us improperly.

13. Changes to this policy

We may update this policy when the website, app, providers, or law changes. The current version and effective date will remain available on this page. For material changes, we will provide additional notice in the app or on the website where reasonably possible.