Privacy policy

1. Who we are

Sheng (“we”, “us”) is a Mandarin pronunciation training app for iPhone and iPad. This policy explains what information the app handles, why, and the choices you have. Questions are always welcome at support@shengchinese.com.

2. Your voice recordings

Sheng's core feature is grading your spoken Mandarin. To do this, the app needs microphone access while you complete speaking exercises.

• Recording happens only when you start a speaking exercise and stops when the exercise ends. The microphone is never on in the background.
• Most scoring runs on your device. Tone, sound, and single-word exercises are analyzed entirely on-device to produce a per-syllable verdict of your pitch and pronunciation. That audio is not sent to any server.
• Connected-speech sentences are scored in the cloud. For the end-of-lesson sentence exercise, your recording — together with the target sentence — is sent to our server, which forwards it to Microsoft Azure's pronunciation-assessment service to grade how clearly you said each syllable. The score is returned and shown to you. We do not store the recording on our servers; Azure processes it to compute the score under its data-processing terms. This audio is used only to score that sentence — never to identify you, never for advertising.
• A recording also leaves your device when you send feedback. If you tap the flag on a score to report it, we receive that one recording, what the app heard, and the score — so we can review and improve grading. This is opt-in: it only happens when you flag a result, and you can turn it off entirely with the “Help improve Sheng” setting.
• Recordings are not used to identify you, are not linked to advertising profiles, and are never sold or shared with third parties for their own purposes (Microsoft Azure acts only as our processor to score a sentence, on our behalf).
• Playback clips you choose to keep (for example, to hear your own progress over time) are stored on your device and can be deleted at any time from within the app.

3. Information we collect

Learning data

Your progress — which sounds you've practiced, mastery per tone, and exercise results — is stored on your device. If you back up your iPhone to iCloud, that progress is included in the Apple-encrypted device backup, which we cannot read. Sheng has no account and does not run its own sync service.

Diagnostics

With your consent via Apple's standard sharing settings, we receive anonymized crash reports and aggregate usage statistics (for example, which exercise types are most used). These contain no audio and no identity.

Purchases

Subscriptions and purchases are processed entirely by Apple. We receive an anonymized receipt confirming your entitlement — never your name, address, or payment details.

4. What we don't do

• We don't sell or rent personal information. To anyone. Ever.
• We don't show third-party ads or use advertising trackers.
• We don't require an account, an email address, or a phone number to learn.
• We don't use your voice recordings to train models without your explicit, separate opt-in (the “Help improve Sheng” setting).

5. Children

Sheng is suitable for general audiences and does not knowingly collect personal information from children under 13. Because no account is required and learning data stays on the device, a child's use of the app does not transmit personal information to us.

6. Data retention & deletion

Because your learning data lives on your device (and in your iCloud device backup, if you make one), deleting the app removes your data from the device. You can also reset all progress from Settings → Reset progress inside the app. If you have contacted support, you may ask us to delete that correspondence at any time.

7. Security

Data stored on your device is protected by iOS's built-in encryption. Any data in transit (such as diagnostics or sentence scoring) is encrypted using TLS.

8. Your rights

Depending on where you live (including the EU/EEA, UK, and California), you may have rights to access, correct, delete, or port personal information, and to object to certain processing. Since almost all data stays under your control on your device, most of these rights are exercisable directly — but we will help with any request at support@shengchinese.com.

9. Changes to this policy

If we make material changes, we will update the date above and notify you in the app before the change takes effect. Continued use after a change means you accept the updated policy.

10. Contact

For anything privacy-related, email support@shengchinese.com with the subject “Privacy”.