Last updated: June 4, 2026.

Privacy Policy

QuiddityML is a mobile-first machine learning education app. This Privacy Policy explains what information QuiddityML collects, how it is used, and how users can delete their account.

Information We Collect

We collect the following information when you use QuiddityML:

• Account information: email address, display name, and optional location.
• Authentication information: sign-in identifiers from Google and Apple.
• Learning data: claimed tracks, lesson progress, exercise attempts, answers submitted, correctness, self-ratings, spaced-repetition state, hearts, streaks, activity dates, and continue positions.
• Feedback: category and message text if you submit feedback through the app.
• Diagnostics: crash reports, error logs, device and app version information through Sentry.
• Payment information: subscription status and purchase identifiers if paid subscriptions are enabled through RevenueCat, Apple, or Google. QuiddityML does not directly store full payment card numbers.
• Notification information: push tokens and notification preferences if push notifications are enabled.

How We Use Information

We use this information to:

• Create and secure your account.
• Save and sync your learning progress across sessions and devices.
• Schedule spaced-repetition reviews.
• Enforce free and Pro access rules.
• Track hearts, streaks, activity, and completion state.
• Respond to feedback and support requests.
• Diagnose crashes, bugs, and performance issues.
• Process subscriptions and restore purchases when payments are enabled.
• Send reminders if notifications are enabled.

Third-Party Services

QuiddityML uses third-party services to operate the app:

• Supabase: authentication, database, Edge Functions, and account data storage.
• Google OAuth: Google sign-in and basic profile information.
• Apple Sign-In: Apple authentication.
• Sentry: crash reporting and diagnostics.
• RevenueCat: subscription entitlement and purchase status if payments are enabled.
• Expo: app build services and push notification delivery if notifications are enabled.
• Resend: transactional email for feedback notifications and confirmations.

These services process information according to their own privacy policies.

Data Retention

We keep account and learning data while your account is active. If you delete your account, QuiddityML deletes your app profile, learning progress, exercise attempts, hearts, streaks, claimed tracks, review settings, and related user-owned app data from our database. Some records may be retained if required for legal, security, fraud-prevention, or payment-dispute reasons.

Account Deletion

You can delete your account in the app:

Profile -> Account -> Delete Account

The app asks you to type DELETE before deletion. Deleting your account permanently removes your QuiddityML account and app data. If you have an active App Store or Google Play subscription, deleting your QuiddityML account may not cancel the store subscription automatically. You may need to manage or cancel the subscription through Apple or Google.

If you cannot access the app, contact us at hello@quiddityml.com.

Data Export

To request a copy of your data, contact us at hello@quiddityml.com. We may need to verify your identity before fulfilling the request.

Children's Privacy

QuiddityML is not intended for children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has provided personal information, contact us so we can review and delete it if appropriate.

International Users

If you use QuiddityML from outside the United States, your information may be processed in countries where our service providers operate. These countries may have different data-protection laws than your country.

Changes To This Policy

We may update this Privacy Policy as QuiddityML changes. If the changes are material, we will provide notice in the app or by another reasonable method.

Contact

Privacy questions: hello@quiddityml.com
Support: hello@quiddityml.com