This Privacy Policy explains what data the AiChinese app ("AiChinese", "we", "us") collects, how we use it, and who processes it on our behalf. Questions: nihao@ai-chinese.app.
What we collect
- Account information — the email address (and any sign-in provider identifier) you use to create and access your account.
- Your learning content — the vocabulary, notes, lessons, study progress, and messages you create or send to the in-app tutor. This is the core data the app exists to store and sync.
- Voice recordings — when you use pronunciation/speaking practice, your microphone audio is recorded and sent to our server for transcription and feedback. See "AI processing" below.
- Notifications token — if you enable notifications, a device push token so we can deliver study reminders.
- Usage and diagnostic data — the screens and features you use and actions you take in the app (e.g. starting a lesson), your device model, operating system and app version, an approximate location (country and city) derived from your IP address, crash reports, and recordings of app sessions. In session recordings all text, typed input and images are masked, so they show layout and taps, never your writing, transcripts or reading. This data is linked to your account. You can turn it off at any time (see "Your rights and choices").
- Support correspondence — anything you send us by email.
We use PostHog for product analytics and Sentry for crash reporting (see below). We do not use advertising or cross-app tracking SDKs, we do not track you across other companies' apps or websites, and we do not sell your data.
How we use it
- To provide and sync your account and learning content across your devices.
- To power AI features — generating practice and lessons, evaluating sentences, and transcribing/scoring your pronunciation.
- To send study reminders you've opted into.
- To understand how the app is used and diagnose crashes, so we can fix problems and improve features.
- To respond to support requests and keep the service secure.
AI processing and service providers
We use the following processors ("subprocessors") to run the app. They process your data only to provide their service to us:
- Supabase — authentication, database, and hosting (stores your account and learning content).
- OpenAI — transcribes your voice recordings (speech-to-text) and powers some AI text features. Audio and text sent via the API are not used to train OpenAI's models.
- OpenRouter — routes some AI text generation (lessons, sentences, tutor replies) to underlying model providers.
- Cloudflare — generates lesson cover images and provides network/infrastructure services.
- Apple — App Store, in-app purchases, and (if used) Sign in with Apple.
- Expo — delivers push notifications.
- PostHog (PostHog Inc., EU-hosted) — product analytics: processes the usage data described above, including masked session recordings, on servers in the EU.
- Sentry — crash and error reporting.
Your learning text and voice audio are sent to these AI providers only to produce the feature you requested (e.g. a transcription or a generated sentence). We do not send your data to advertisers or data brokers.
Data retention
We keep your account and learning content for as long as your account exists. Voice recordings are processed to produce feedback and are not retained beyond what's needed to deliver and improve that feature. You can delete your content or your entire account at any time (see below); deletion removes your data from our active systems.
Your rights and choices
- Access / export — contact us to request a copy of your data.
- Delete your account — you can delete your account and associated data from within the app (Settings → Account), or by emailing us. Deletion is permanent. Full instructions, and what is and isn't removed, are on our account deletion page.
- Notifications — you can disable reminders in your device settings at any time.
- Usage data — turn off Settings → Share usage data in the app to stop usage analytics and session recordings.
Depending on where you live (e.g. UK/EU under UK GDPR/GDPR, or California under the CCPA/CPRA), you may have additional rights to access, correct, delete, or restrict processing of your data. Contact us to exercise them.
Children
AiChinese is intended for a general audience and is not directed at children under 13. We do not knowingly collect personal data from children under 13. If you believe a child has provided us data, contact us and we will delete it.
Security
We use industry-standard measures (encrypted transport, access controls via our hosting provider) to protect your data. No method of transmission or storage is completely secure, but we work to protect your information.
Changes
We may update this policy as the app evolves. Material changes will be reflected by a new effective date at the top, and where appropriate, an in-app notice.