Privacy Policy
Effective June 10, 2026
This policy describes what ToneYin collects and how it is used. It covers the ToneYin iOS app and the website at toneyin.ai (together, “ToneYin”). ToneYin grades your Mandarin pronunciation: you record short prompted phrases, and we analyze the audio to give you per-syllable tone and pronunciation feedback.
Information we collect
- Audio recordings. When you tap record, we capture your microphone audio of the prompted phrase. The microphone is only active while you are recording. Recordings are uploaded to our servers for grading and stored with your account (in the app) or your practice session (on the website).
- Account information. The app uses Sign in with Apple, which shares your name and email address with us (you can choose Apple’s Hide My Email to share a private relay address instead). We also assign your account a random user ID.
- Learning activity. Your graded attempts, scores, streaks, and lesson progress are stored with your account so the app can show your history and progress.
- Website demo information. The toneyin.ai demo asks for optional self-reported details (such as your name, native language, and other languages you speak) to label your recordings, and an optional email address if you want product updates.
- Usage analytics. We collect basic product events (for example: lesson started, recording graded, lesson completed) along with your user ID and device platform, so we can understand how ToneYin is used. Analytics never include your audio.
- Crash reports. If the app crashes or hits an error, a diagnostic report (device model, OS version, and technical details of the failure) is sent to us so we can fix it.
How we use your information
- To grade your pronunciation and show you feedback.
- To keep your practice history, streaks, and progress.
- To improve ToneYin’s pronunciation-grading models. Recordings may be reviewed, labeled, and retained for research and development, as described in the consent notice shown before you record.
- To diagnose crashes and fix bugs.
- To send you product updates, only if you opted in with your email.
What we don't do
- We do not sell your personal information.
- We do not show ads or share your data with advertisers.
- We do not use your recordings for anything beyond providing and improving ToneYin.
Service providers
ToneYin runs on third-party infrastructure that processes data on our behalf: Supabase (authentication, database, and recording storage), Cloudflare (recording storage for the website demo), Modal (audio analysis), Fly.io (API hosting), Vercel (website hosting), PostHog (analytics), Sentry (crash reporting), and Apple (Sign in with Apple). Each provider receives only the data needed for its function.
Retention and deletion
Account information and learning activity are kept while your account is active. Recordings may be retained for model research and development. You can request deletion of your account, recordings, and all associated data at any time by emailing hello@toneyin.ai, and we will delete it within 30 days.
Children
ToneYin is not directed at children under 13, and we do not knowingly collect personal information from them. If you believe a child has provided us personal information, contact us and we will delete it.
Changes to this policy
If we make material changes to this policy, we will update this page and revise the effective date above.
Contact
Questions about this policy or your data: hello@toneyin.ai.