Privacy Policy

Effective date: July 7, 2026

1. Introduction

MandarinAI ("we," "our," or "us") operates the Mandarin-learning platform at mandarin-ai.com. This Privacy Policy explains, in plain language, what information we collect, why we collect it, who processes it on our behalf, and the choices you have. We collect only what we need to run the service — nothing more.

2. Information We Collect

Account data

When you create an account with your email address, we store your name (if you provide one), email address, and a hashed password. When you sign in with Google, we receive your name, email address, and profile picture from your Google account instead (see section 3 below).

Learning data

To make spaced repetition work, we record your study activity:

  • The words and word lists you study
  • Your review history and per-card scheduling state (the FSRS algorithm's memory model of what you know)
  • Study sessions, including timing and ratings
  • Stories and lessons you generate within the app

Billing status

Payments are handled by Polar, our merchant of record. We store only your subscription status (which plan you are on and whether it is active). We never see or store your card number or other payment details.

Emails we send

We send transactional emails — account verification, password reset, and trial notices — through Cloudflare's Email Service. We do not send marketing emails without your consent.

Cookies and analytics

We use essential cookies to keep you signed in (session cookies). We do not currently run third-party advertising trackers on the site.

3. Google User Data

If you choose to sign in with Google, we receive your name, email address, and profile picture from your Google account. Here is exactly how we handle that data:

  • We store it in our database solely to create and operate your MandarinAI account (identifying you when you sign in, showing your name and picture in the app, and contacting you about your account).
  • We do not use Google user data for advertising of any kind.
  • We do not sell Google user data, and we do not transfer it to third parties except to the service providers listed in section 5, who process it only on our instructions to run the service.
  • Humans at MandarinAI do not read this data, except when needed for support or security purposes with your consent, or where required by law.

MandarinAI's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

4. How We Use Your Information

We use the information above to:

  • Operate your account and keep you signed in
  • Schedule your reviews and track your learning progress
  • Generate the stories, lessons, and audio you request
  • Manage your subscription and free trial
  • Send you account emails (verification, password reset, trial notices)
  • Respond to your support requests
  • Keep the service secure and comply with the law

5. Service Providers

We do not sell your personal information. We share data only with the following providers, each of which processes it on our behalf to run the service:

  • Cloudflare — hosts the application and delivers our transactional emails
  • PlanetScale — hosts our database, where your account and learning data are stored
  • Polar — processes payments as merchant of record (they receive your email and billing details; we never see card numbers)
  • Anthropic — generates stories and lessons with AI; we send only the learning content you request (such as the words to include), never your identity
  • Replicate — generates pronunciation audio from the Chinese text you are studying
  • Microsoft Azure — synthesizes speech for the text-to-speech reader from the Chinese text you are studying

We may also disclose information when required by law, or in connection with a merger or acquisition (in which case this policy continues to apply to your data).

6. Data Retention and Deletion

We keep your account and learning data for as long as your account exists, because your review history is what makes spaced repetition work. You can delete your account yourself at any time from your account settings (Account → Delete Account). Deleting your account immediately cancels any active subscription and signs you out everywhere, and your account is deactivated right away. For 30 days afterwards you can restore it — with all of your data intact — using the link we email you when you delete. After those 30 days, your personal and learning data (including your review history, study sessions, and saved stories) are permanently erased and cannot be recovered. If you would rather we do it for you, email us at support@mandarinai.com or use our contact page. Either way, we may retain the limited records we are legally required to keep (for example, billing records).

7. Data Security

All traffic to mandarin-ai.com is encrypted with TLS. Passwords are stored hashed, never in plain text. Access to production data is limited to what is needed to operate the service. No method of transmission or storage is 100% secure, but we work to protect your information against unauthorized access, alteration, disclosure, or destruction.

8. Your Rights and Choices

Depending on where you live, you may have the right to:

  • Access a copy of your personal information
  • Correct inaccurate information
  • Delete your personal information
  • Receive your data in a portable format
  • Object to or restrict certain processing

To exercise any of these rights, email support@mandarinai.com. We respond to all requests, typically within 30 days.

9. Children's Privacy

Our service is not directed at children under 13, and we do not knowingly collect personal information from children under 13. If we learn that we have, we will delete it.

10. International Data Transfers

Our infrastructure runs in the United States (application hosting and database), so your information may be processed outside your own country. Where required, we rely on appropriate safeguards for such transfers.

11. Changes to This Privacy Policy

We may update this Privacy Policy from time to time. We will post any changes on this page and update the effective date above. For material changes, we will also notify you by email or in the app.

12. Contact Us

Questions about this policy or your data? Email us at support@mandarinai.com or use our contact page. We typically respond within 24 hours.