MUSU ("we") operates MU:note, an automatic practice-tracking app for musicians ("Service"). We collect as little as possible — the app only records what it observes about your practice, nothing more.
| Type | Items | When |
|---|---|---|
| Required (sign-up) | Kakao/Apple account identifier, email (when provided by your social account) | When you sign up |
| Optional (sign-up) | Age group, gender, school | Only if you enter them |
| Service use | Practice records (start/end time, practice and away time, instrument, practice type, piece names/notes/reflections you type), device language, timezone, app settings | While using the app |
| Automatically generated | Detection program version, pause/away counts, generated encouragement notes, record created/updated timestamps, consent time and version | While using the app |
| Service operation records | What happened when something failed (error type and code, counts such as how many records were waiting to upload), app and iOS version, app language and instrument setting, whether reminders are on | When an error occurs, plus once a day |
Service operation records exist so we can find the cause when something goes wrong — for example, "I practiced but nothing was recorded." Piece names, notes, and reflections you type are never included, and both the app and the server filter them out mechanically. These records are deleted automatically after 90 days, and they are removed along with everything else if you delete your account, regardless of that period.
Guest (not signed-up) practice records are also stored on our server for syncing. They are not linked to an account, so access is lost once the app is deleted; such orphaned records will be cleaned up periodically.
What we never collect: the app uses your microphone to detect practice sounds, but raw audio is never stored or transmitted under any circumstances. Sound is classified on your device ("is this an instrument?") and immediately discarded. We do not access your location, contacts, or photos.
When generating encouragement notes, only summarized practice statistics (such as practice time, weekday, and time-of-day patterns), practice types, and your app language are sent for AI processing — your typed notes and piece names are never sent. This only happens when generating notes for signed-in members. Nothing is sent for AI processing while you use the app without an account, and the first welcome note is created on your device without any external transfer.
| Processor | Purpose | Location |
|---|---|---|
| Supabase | Data storage and authentication | South Korea (Seoul region) |
| Anthropic | Generating encouragement notes (statistics only) | United States |
You can view your data (in the app), edit it (in the app), delete it (account deletion), and contact us below with any privacy request.
The Service is not available to children under 14. Sign-up requires confirming you are 14 or older.
We use encryption in transit (HTTPS), per-account access control (you can only access your own data), and the principle of least privilege.
Privacy officer: MUSU founder · j204002@gmail.com