Privacy Policy

Effective date: May 8, 2026 · Last updated: May 8, 2026

BookStreak ("the App") is built by Kian Nguyen ("we", "us"). Privacy is not a feature we bolt on — it's a design constraint. This policy describes what data we collect, how we use it, and your rights.

1. What we store on your device

Your books, reading sessions, reflections, streaks, identity labels, and settings live in a local SQLite database on your phone. If you use BookStreak as a guest, that is the only place your reading data exists. We cannot access it.

2. What we store in the cloud (only if you sign in)

Signing in with Apple, Google, or email enables cloud backup via Supabase so you can restore your library on a new device. We store:

• Your email address and display name (for account management)
• Your encrypted library data (books, sessions, streaks, settings)
• Authentication tokens (managed by Supabase Auth)

Cloud sync is optional. You can use every feature of BookStreak without creating an account.

3. What we do NOT collect

• Anonymous product analytics only. We use Mixpanel to track anonymous funnel events (app opens, onboarding steps) to improve BookStreak. No book titles, page counts, or personal reading content is ever sent. You can opt out anytime in Settings.
• No ad networks. No ads, no ad tracking, no ad identifiers.
• No social tracking pixels. No Facebook Pixel or equivalent.
• No location data. We do not request or store your location.
• No contacts or phone data. We do not access your contacts, call logs, or messages.
• No selling or sharing of data. Your data is never sold, rented, or shared with third parties for advertising or profiling.

4. AI runs on your device

BookStreak's AI features (session reflections, pattern coaching, reading-history recaps) run entirely on your device using Apple Foundation Models (iOS 26+). Your reading data never leaves your phone to power AI features. There is no cloud AI fallback. No data is sent to OpenAI, Anthropic, Google, or any other AI provider.

5. Third-party services

BookStreak connects to these services, and only these services:

• Supabase — cloud sync and authentication (opt-in). Supabase Privacy Policy
• RevenueCat — subscription management. Receives your anonymous app user ID and purchase receipts. RevenueCat Privacy Policy
• Mixpanel — anonymous product analytics (opt-out available in Settings). Receives anonymous funnel events only — no reading data, no PII. Mixpanel Privacy Policy
• Open Library API & Google Books API — book search. Your search queries are sent to these services to find book metadata. No personally identifiable information is included.
• Apple / Google authentication — if you choose to sign in with Apple or Google. We receive your name, email, and account ID only.

6. Data retention

Local data exists on your device until you delete it or uninstall the app. Cloud data is retained as long as your account exists. When you delete your account (Settings → Account → Delete Account), all cloud data is permanently removed within 30 days.

7. Your data rights

Regardless of where you live, you can:

• Export your entire library as CSV or JSON at any time, free of charge (Settings → Export)
• Delete all local data, cloud data, and your account from Settings → Privacy
• Access a copy of your cloud-stored data by emailing us

If you are in the EU/EEA (GDPR), California (CCPA/CPRA), or another jurisdiction with data protection laws, you have additional rights including the right to rectification, restriction of processing, and lodging a complaint with a supervisory authority. We respond to all data requests within 30 days.

8. Children's privacy

BookStreak is rated 4+ and does not knowingly collect personal information from children under 13 (or the applicable age in your jurisdiction). If you believe a child has provided us with personal data, contact us and we will delete it.

9. Changes to this policy

We may update this policy from time to time. Material changes will be communicated via in-app notification. The "last updated" date at the top reflects the most recent revision.

10. Contact

Questions or data requests? Email support@bookstreak.quest. We reply within 48 hours.