Privacy Policy
Effective July 28, 2026
Mayu is a language-learning app. This policy explains what information the app stores, why, and the control you have over it. We keep it short because the app does not do much with your data: it runs Mayu, and it shows us which parts people actually use.
What we store
Your account. When you sign up we store your email address so you can sign in. Your password is handled by our authentication provider and stored only in a securely hashed form; we never see or store it in plain text.
Your learning data. The cards you create, your reviews and ratings, scheduling state, streak, XP, and your settings (daily goal, target retention, chosen language). This is what lets the app remember your progress and schedule your reviews.
How you use the app. Which screens you open and which actions you take (signing in, adding a card, finishing a review), plus a recording of what happens on screen while you are in the app. Anything you type into a box is hidden before that recording leaves your device, so your password and your typed answers are not in it. This is tied to your account, so we can tell one person's sessions from another's.
How we use it
To run the app for you: to sign you in and to save, sync, and schedule your learning across your devices.
And to make the app better. Seeing which screens people open, where they get stuck, and where they give up is how we decide what to fix next. That is the whole of it. We do not use it for advertising and we do not sell it.
What we do not do
- We do not sell or rent your data to anyone.
- We do not show ads or use advertising trackers.
- We do not track you across other apps or websites, and we share nothing with data brokers.
- We do not use your learning content to train models, and we do not build a profile of you for anyone outside Mayu.
Where your data lives
Your data is stored with our infrastructure providers: Supabase (database and authentication), Vercel (app hosting), and PostHog (usage analytics and screen recordings, stored in the United States). They process data on our behalf to keep the app running and apply their own industry-standard security. Data may be processed on servers outside your country.
Deleting your data
You can delete your account at any time from Settings - Danger zone - Delete account. This permanently and immediately erases your account and all associated data: your cards, reviews, progress, settings, and your usage history and screen recordings. It cannot be undone, and we keep no backup copy of deleted accounts.
Children
Mayu is not directed at children under 13, and we do not knowingly collect data from them.
Changes to this policy
If this policy changes we will update the effective date above. For material changes we will surface a notice in the app.
Contact
Questions about your data? Email support@trymayu.com.
