Privacy Policy
Last updated: September 18, 2026
Book Club+ (“the app”) is made by Lazarus Labs (“we”, “us”). This policy explains what the app collects, why, who helps us run it, and the choices you have.
The short version
- You can use Book Club+ without an account. The app gives you an anonymous guest ID so your library can be saved.
- We store your reading data (your library, lists, ratings, notes, goals and AI Chat conversation) so the app can work and sync.
- If you use AI Chat, your messages and a summary of your reading taste are sent to OpenAI to understand what you're looking for. We ask before anything is sent.
- The free version shows ads from Google AdMob. Where the law requires it, we ask for your consent first; on iPhone, Apple asks whether you allow tracking.
- You can delete everything at any time from Settings → Delete Account (or Delete My Data as a guest).
- We don't sell your personal information.
1. What we collect
Account information
- An anonymous user ID, created the first time you open the app.
- If you create an account: your email address, and the name and profile icon you choose. With Sign in with Google we receive your Google account's email and name; with Sign in with Apple we don't request your name or email, and Apple may give us a private relay address instead.
Your reading data
- Books on your shelves and their reading status, favorites, ratings, feedback (“not for me”), start and finish dates, reading progress and private notes.
- Your lists, reading goals, favorite genres and authors, and the books you picked during setup.
- A taste profile we compute from the above to recommend books.
- Your AI Chat conversation (your messages and the books suggested), so you can continue it later.
Activity in the app
- Books you open and searches that lead you to a book (the search text and the book), linked to your user ID. We use these, with shelving and ratings, to build anonymous community rankings such as Trending and Hidden Gems. Other readers never see who did what.
Purchases
- If you buy Remove Ads, we receive the store's transaction record (a transaction or order ID and the product) to verify the purchase, restore it later, and turn ads back on if the purchase is refunded. Apple and Google tell us about refunds of it. Payment is handled entirely by Apple or Google; we never see your card details.
Advertising data
- Google AdMob, which shows ads in the free version, may collect device identifiers (such as your advertising ID, if you allow it), IP address, approximate location derived from it, and ad interactions. See how Google uses information from apps.
Device and security data
- Firebase App Check confirms requests come from the genuine app, using Apple App Attest / DeviceCheck or Google Play Integrity.
Kept only on your device
- Recent searches, reading reminder settings, your theme choice and whether you've agreed to AI Chat's data sharing. Reading reminders are scheduled on your device; we don't send them.
We don't use analytics or crash-reporting SDKs, and we don't collect your contacts, photos, precise location or health data.
2. How we use it
- To run the app: save and sync your library, show your shelves, lists and stats, and restore your purchase.
- To recommend books and answer AI Chat requests.
- To build anonymous community rankings.
- To show ads in the free version, and to measure and limit them.
- To keep the service secure and prevent abuse (for example, daily limits on AI Chat and book searches).
- To answer you when you contact support, and to review AI answers you report.
3. AI Chat and OpenAI
AI Chat is powered by OpenAI. Before your first message, the app asks for your permission. When you send a message, we send OpenAI:
- the messages in your current conversation, and
- a summary of your reading taste: favorite genres and authors, and books you've rated, are reading, have finished or didn't like.
We never send your name, email or account details. Requests carry a one-way hashed identifier so OpenAI can detect abuse without knowing who you are. Under OpenAI's API terms, this data isn't used to train its models; OpenAI may keep it for a limited time to monitor for abuse. Answers are generated by AI and can be wrong; every recommended book comes from Google Books. You can report an answer from the flag under it, which sends us that answer, the books it suggested and the message it answered.
4. Who helps us run Book Club+
We share data only with service providers that process it for us:
| Provider | What for |
|---|---|
| Google Firebase / Google Cloud (US) | Accounts, database, server functions, App Check |
| Google Books | Book information and covers (our server sends your search terms, not your identity) |
| Google AdMob and Google's consent tools | Ads in the free version, and ad consent |
| OpenAI | AI Chat |
| Apple and Google Play | Sign-in and in-app purchases |
We may also disclose information if required by law, or to protect the rights and safety of our users or others. We don't sell personal information, and we don't share it for cross-context behavioral advertising except through AdMob as described above, subject to your consent and tracking choices.
5. Your choices
- Tracking and ad consent (iPhone and EEA/UK): you can decline when asked, and change your ad choices any time in Settings → Ad Privacy Choices (shown where required). On iPhone you can also turn off tracking in iOS Settings → Privacy & Security → Tracking.
- Remove ads: a one-time purchase stops all ads.
- AI Chat: it's optional, and nothing is sent until you agree.
- Notifications: reading reminders are off unless you turn them on.
6. Keeping and deleting your data
We keep your data while you use the app. You can delete it at any time:
- In the app: Settings → Delete Account (or Delete My Data as a guest). This permanently deletes your account, library, lists, ratings, notes, goals, AI Chat history and taste profile, removes your ratings from community rankings and unlinks your activity from them (anonymous counts already folded into a ranking stay), and releases any purchase so it can be restored to a new account. (A refunded purchase's transaction record stays, no longer linked to you, so it can't remove ads again.) If you signed in with Apple, we also revoke the app's access to your Apple ID.
- Without the app: contact us through https://thelazaruslabs.com/support from the email on your account (or tell us you used a guest account) and we'll delete it within 30 days.
Cached book information from Google Books isn't personal data and expires on its own.
7. Children
Book Club+ isn't directed to children under 13, and we don't knowingly collect their personal information. If you believe a child has given us information, contact us and we'll delete it.
8. Where your data is stored
Your data is stored on Google Cloud servers in the United States. If you use the app from elsewhere, your information is transferred to and processed in the US.
9. Security
Data is encrypted in transit, access is restricted to your account by our database rules, and server keys (such as for Google Books and OpenAI) never leave our servers. No system is perfectly secure, but we work to protect your information.
10. Changes
If we change this policy, we'll update the date above, and for significant changes we'll let you know in the app.
11. Contact
Questions or requests: https://thelazaruslabs.com/support