Effective Date: February 24, 2026
MentalMather ("we," "our," or "the app") is a mental math training application. We are committed to protecting your privacy. This policy explains what data the app collects, how it is used, and your choices.
| Data | Stored Where | Purpose |
|---|---|---|
| Anonymous device identifier (UUID) | Your device + our server | Link your sessions, challenges, and analytics without identifying you personally |
| Display name (optional, user-chosen) | Your device + our server (challenges only) | Show your name to challenge opponents. You may be prompted to set this before your first challenge; you can skip or change it later. |
| Game performance data (scores, times, problem attempts) | Your device only | Calculate your Sharpness Score and track personal progress. This data never leaves your device. |
| Challenge results (scores and completion status) | Your device + our server | Enable multiplayer challenge comparisons between players |
| App usage analytics (screens visited, features used, session durations) | Your device + our server | Improve the app experience. Events are queued locally and uploaded in batches. |
| A/B test assignments | Your device + our server | Test feature variations to improve the app. Assignments are cached locally for offline use. |
| App settings preferences (theme, haptics, display options) | Your device only | Remember your preferences. This data never leaves your device. |
| Subscription status (Premium) | Your device (via Apple/Google) | Determine whether to show advertisements. We do not receive or store your payment details — all transactions are processed by Apple or Google. |
We do not collect your real name, email address, phone number, location, contacts, photos, or any other personally identifiable information. You do not need to create an account or sign in to use the app. We do not receive or have access to your payment information — all purchases are handled entirely by Apple or Google.
Google AdMob (free tier only) — We display interstitial ads through Google AdMob. Ads appear only between screens, never during gameplay. Google may collect device identifiers (such as your Advertising ID), IP address, and general device information to serve and personalize ads. This data is governed by Google's Privacy Policy. You can opt out of personalized ads through your device settings (Settings → Privacy → Ads on Android; Settings → Privacy & Security → Tracking on iOS). MentalMather Premium subscribers are not shown ads, and no ad-related data is collected for them.
Apple App Store / Google Play — If you purchase MentalMather Premium, your payment is processed entirely by Apple or Google. We receive only a confirmation of your subscription status (active or expired) — never your payment method, billing address, or other financial details. Your purchase is governed by Apple's Terms or Google Play's Terms.
Supabase — We use Supabase to store challenge data, analytics events, and feature flag assignments. All data is associated with your anonymous device UUID only — never with personally identifiable information. Supabase's privacy policy is available at supabase.com/privacy.
The majority of your data is stored locally on your device and never transmitted to any server. Data that is sent to our server (challenges, analytics, feature flags) is transmitted over encrypted connections (HTTPS) and associated only with your anonymous device identifier. We do not sell, share, or provide your data to any third party other than the service providers listed above.
Local data remains on your device until you uninstall the app or clear its data. Server-side data is retained as follows:
You can request deletion of all server-side data associated with your device identifier by contacting us (see below).
MentalMather is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child under 13 has provided data through the app, please contact us and we will promptly delete it.
We may update this policy from time to time. Changes will be posted on this page with an updated effective date. Continued use of the app after changes constitutes acceptance of the updated policy.