Last updated: July 23, 2026
The short version: your practice data stays in your browser unless you create an account to sync it. We collect anonymous, aggregate usage statistics (which features get used, what exercises people ask for) to understand what's useful — no account, no personal data, and you can switch it off with your browser's Do Not Track setting. With an account, we store your email and your practice progress so we can sync it across your devices. We don't sell data, we don't run third-party ad trackers, and you can delete your account and all its data yourself at any time.
All app data — practice logs, personal bests, ear-training stats, settings — is stored in your browser's local storage on your device. It is never transmitted to us. Clearing it from the Progress tab or clearing your browser data removes it completely.
If the app crashes in your browser, an automatic report may be sent containing the technical error message and your browser's user-agent string. These reports contain no personal information, no account identifiers, and none of your practice data — they exist only so bugs get noticed and fixed.
To learn what's actually useful, the app records anonymous, aggregate usage events — for example, which tabs you open, what you type into the plain-English exercise and progression boxes (the music request itself, e.g. "A minor scale 3 notes per string"), and roughly how long a visit lasts. Each browser gets a random id so we can tell a returning visit from a new one; it is not linked to your name, email, or account, and it contains none of your practice-log data. This runs whether or not you have an account.
Turning it off: if your browser sends a Do Not Track signal, nothing is recorded. There are no third-party analytics services and no third-party cookies — the data goes only to our own Supabase backend.
No advertising trackers and no third-party cookies. Signed-in sessions and the anonymous-visitor id are kept in your browser's local storage. If this ever changes (for example, if the app adds ads), this policy will be updated first.
Open the account menu in the app and choose Delete account — this immediately and permanently removes your account, email, and all synced progress from our database. Local data on your devices stays with you. You can also email us (below) and we'll delete it for you.
Questions or requests: patrickdleduc@gmail.com, or open an issue on GitHub.