Privacy Policy for Math Teacher

Last updated: September 2, 2026

1. Introduction

Math Teacher ("we", "our", "the app") is committed to protecting your privacy. This policy explains how we collect, use, and protect your information when you use our AI-powered math question generator.

2. Information We Collect

Account Information

• Email address: Required for account creation and login via Supabase Auth
• User ID: Anonymous identifier for cloud data sync

Usage Data

• Question generation parameters: Competition type, grade, topic, difficulty selected
• Question usage: Number of questions generated per day (to enforce free tier limits)
• Generated questions: Stored in your personal cloud library

Data We DO NOT Collect

• Student names or personal information
• Payment information (handled securely by Google Play)
• Device location
• Contacts or photos
• Browsing history outside the app

3. How We Use Your Information

• Account management: Enable login and sync your question library across devices
• Service delivery: Generate AI questions via DeepSeek API
• Usage limits: Enforce free tier quota (5 questions/day)
• App improvement: Analyze anonymous usage patterns to improve features
• Support: Respond to your inquiries and troubleshoot issues

4. Data Storage and Security

• Cloud storage: User data stored securely on Supabase (PostgreSQL with Row-Level Security)
• Encryption: All data transmitted via HTTPS/TLS
• Access control: Only you can access your generated questions
• Data retention: Account data kept until user requests deletion
• Backups: Regular automated backups for data integrity

5. Third-Party Services

Supabase (Backend)

• Purpose: User authentication and question storage
• Data shared: Email, user ID, generated questions
• Privacy Policy: https://supabase.com/privacy

DeepSeek API (AI Provider)

• Purpose: Generate math questions using AI
• Data shared: Question parameters only (competition, grade, topic, difficulty)
• Personal info shared: None

Google Play Services

• Purpose: App distribution and updates
• Privacy Policy: https://policies.google.com/privacy

6. Your Rights

You have the right to:

• Access your data: Request a copy of your stored information
• Correct your data: Update inaccurate information
• Delete your data: Request permanent deletion of your account and all associated data
• Export your data: Download your generated questions in portable format
• Withdraw consent: Stop using the service at any time

To exercise these rights, email us at: hello@shangling.tech (or your actual support email)

7. Children's Privacy

Math Teacher is designed for teachers and educators (18+), not children. We do not knowingly collect information from users under 13. If you believe a child has provided us with personal information, please contact us immediately at hello@shangling.tech.

8. Data Sharing

We DO NOT:

• Sell your personal information to third parties
• Rent or lease your data for marketing purposes
• Share your questions with other users
• Use your data for advertising targeting

We may share data only when:

• Required by law or legal process
• Necessary to protect our rights or safety
• You explicitly consent to sharing

9. International Users

Your data may be stored on servers located in the United States (Supabase infrastructure). By using Math Teacher, you consent to the transfer of your information to these locations. We ensure appropriate safeguards are in place for international data transfers.

10. GDPR Compliance (European Users)

For users in the European Economic Area (EEA):

• Legal basis: We process data under legitimate interest and consent
• Withdraw consent: You may withdraw consent at any time
• Data portability: You have the right to receive your data in a portable format
• Right to erasure: You may request deletion of your data ("right to be forgotten")
• Supervisory authority: You may lodge complaints with your local data protection authority

11. California Privacy Rights (CCPA)

California residents have additional rights:

• Right to know what personal information is collected
• Right to know if personal information is sold or disclosed
• Right to opt-out of sale (we don't sell data)
• Right to deletion
• Right to non-discrimination for exercising privacy rights

12. Data Breach Notification

In the event of a data breach affecting your personal information, we will:

• Notify affected users within 72 hours
• Describe the nature of the breach
• Provide steps to mitigate potential harm
• Report to relevant authorities as required by law

13. Changes to This Policy

We may update this privacy policy from time to time. Changes will be posted on this page with an updated "Last updated" date. Significant changes will be communicated via:

• In-app notification
• Email to registered users

Continued use of the app after changes constitutes acceptance of the updated policy.

14. Contact Us

For privacy questions, data requests, or concerns:

• Privacy inquiries: hello@shangling.tech
• General support: hello@shangling.tech
• App developer: Math Competition Team

Please allow 7-14 business days for data request responses.