Privacy Policy

Last updated: 21 June 2026

MathVis ("we", "our", or "us") is a free educational maths formula learning app available at postlister.com/mathvis and as an Android app via the Google Play Store. We are committed to protecting your privacy.

1. Information We Collect

• No account required: MathVis does not require you to create an account or log in.
• Usage data: We may collect anonymous, aggregated usage data (page views, feature usage) to improve the app. This data cannot be used to identify you.
• Community videos: If you suggest a video, we temporarily store a hashed version of your IP address (not the raw IP) and a device token (a random identifier stored in a cookie) to prevent spam. We do not store your IP address in plaintext, ever.
• Cookies: We use a single first-party cookie (mv_device) only when you interact with the community video voting and suggestion features. This cookie contains a random identifier, not personal information. It is never shared with third parties.
• Local storage: Some preferences (bookmarks, theme, settings) are stored locally in your browser or device and are never transmitted to our servers.

2. Third-Party Services

• YouTube: Some videos are hosted on YouTube. When you play a YouTube video, YouTube's own privacy policy applies.
• Google Fonts: We use Google Fonts for typography. Google may log font requests; see Google's privacy policy for details.
• AI Solve feature: If you use the AI-powered step solver, your maths question is sent to Google Gemini API. No personal data is attached.

3. How We Use Information

We use the limited data we collect solely to operate and improve MathVis — to prevent spam on the community video features, and to understand which parts of the app are most useful.

4. Data Retention

Hashed IP addresses and device tokens used for rate-limiting are automatically deleted after 30 days. No other personal data is stored on our servers.

5. Children's Privacy

MathVis is designed for students of all ages, including children under 13. We do not knowingly collect any personal information from children. The app does not require login, does not display ads, and does not share any data with advertising networks.

6. Your Rights

You may request deletion of any data associated with your device token by contacting us at the address below. Because we store only hashed identifiers (not names, emails, or raw IPs), we cannot link a deletion request to an individual without the device token from your browser.

7. Changes to This Policy

We may update this policy from time to time. Changes will be posted on this page with a new "Last updated" date.

8. Contact

For any privacy-related questions, please contact us through postlister.com.