Privacy Policy
Unlock Chinese · Last updated 20 July 2026
Unlock Chinese is an iOS app that helps you build a daily Chinese-vocabulary habit by keeping selected apps on your iPhone locked until you finish your study session for the day.
This policy explains exactly what data the app handles, why, and what control you have over it.
The short version. Unlock Chinese stores your email address and your Chinese-learning progress so that it survives if you change or reset your phone, and it records anonymous-by-default product analytics so we can see which parts of the app work and which don't. It contains no advertising, no data brokers, and no cross-app or cross-website tracking. It never sees which apps are installed on your device, and the apps you choose to lock never leave your iPhone. You can delete your account and all associated data from inside the app at any time.
Who is responsible for your data
Lucas Liu, an individual developer, is the controller of the personal data described in this policy.
- Contact: 888lucasliu@gmail.com
What Unlock Chinese collects
1. Account identity
Signing in is required so that your progress can be restored on a new or reset device. You sign in with Sign in with Apple or Google. Unlock Chinese never asks for or stores a password.
- Email address — used to identify your account and to contact you about the service if necessary. If you use Sign in with Apple and choose "Hide My Email", we only ever receive Apple's private relay address, never your real one.
- An account identifier issued by Apple or Google — used to link your sign-in to your saved progress.
2. Learning data
This is the substance of the app, and it is stored against your account so it can be restored:
- Your chosen HSK level and study settings (question directions, new words per day, and similar preferences).
- Your progress on each vocabulary word — its review stage and when it is next due.
- A record of each graded answer (which word, correct or incorrect, and when), used to compute your streak, accuracy and study statistics.
- Your current streak and the day you last completed a session.
3. Product analytics
To understand how the app is used and to improve it, Unlock Chinese records analytics events using PostHog, an analytics provider acting on our behalf. This covers things like:
- Which screens you open and which features you use (for example: starting a session, completing a session, opening settings, viewing the subscription screen).
- Technical context sent with each event: a randomly generated device or user identifier, app version, device model, operating system version, and general region or language.
- Diagnostic information about errors and failures, so that bugs can be found and fixed.
Analytics events are linked to your account identifier so that behaviour can be understood across your own devices. They are not used for advertising, are not sold, and are never shared with data brokers or ad networks.
You can turn analytics off at any time in Settings → Privacy → Share usage data. Turning it off does not limit any feature of the app.
4. Subscription status
If you subscribe to Unlock Chinese Pro, our payments provider records that your account holds an active subscription, along with the product purchased and its renewal or expiry date.
Payment is processed entirely by Apple. Your card number, billing address and other payment details are handled by Apple under Apple's own privacy policy and are never transmitted to, or visible to, Unlock Chinese.
What Unlock Chinese does not collect
- No advertising, and no tracking across other companies' apps or websites. No advertising identifier (IDFA) is requested or used. No data is shared with data brokers, ad networks, or any third party for marketing purposes.
- No location, contacts, photos, microphone, camera, health or browsing data. The app does not request these permissions.
- No list of the apps installed on your device. iOS provides no such capability to apps of this kind, and Unlock Chinese does not attempt to obtain one.
- No recording of what you type, beyond your answers to the vocabulary questions themselves.
Screen Time and the apps you choose to lock
Unlock Chinese uses Apple's Family Controls, Managed Settings and Device Activity frameworks to shield the apps you select until your daily session is complete. This deserves a specific explanation, because it is the most sensitive-sounding part of the app:
- When you pick apps to lock, iOS presents Apple's own system picker. The developer never sees your choices. iOS hands the app only opaque tokens, which cannot be read to reveal an app's name or identity.
- Those tokens are stored only on your device. They are never uploaded, never synced to our servers, and never shared with anyone.
- The Screen Time permission is used solely to shield the apps you selected. It is not used to observe, record or report your usage of any app.
Where your data is stored, and who processes it
Data is stored primarily on your device. The app is designed to work offline; syncing to the cloud is a backup and restore mechanism, not a requirement for use.
| Provider | What it handles | Why |
|---|---|---|
| Supabase | Your email, account identifier, learning progress and answer history | Database and authentication hosting, so your progress survives a device change. Access is restricted by row-level security so each account can read and write only its own rows. |
| PostHog | Analytics events and the technical context described above | Product analytics, so we can see which features are used and where the app fails. |
| RevenueCat | Your account identifier and subscription status | Verifying with Apple whether your subscription is active. |
| Apple | Sign in with Apple, and all payment processing | Authentication and App Store billing, under Apple's privacy policy. |
| Google Sign-In, if you choose that method | Authentication, under Google's privacy policy. |
These providers act as processors on our behalf and are not permitted to use your data for their own purposes. Data is transmitted over encrypted connections (HTTPS/TLS) and stored encrypted at rest by the providers above.
Where processing happens. Your account and learning data are stored in the European Union (Ireland), and analytics are processed on PostHog's EU cloud, hosted in the European Union (Germany). Both were chosen deliberately so that your data stays within the EU/EEA and no third-country transfer is required.
Subscription status is processed by RevenueCat in the United States, and Apple and Google process sign-in data and payments under their own privacy policies. These transfers are covered by those providers' standard contractual clauses or an equivalent safeguard.
Legal basis for processing (EU/EEA and UK users)
- Performance of a contract — storing your account and learning progress is what the app is for, and is necessary to provide it to you.
- Consent — product analytics, which you can withdraw at any time in Settings without losing any functionality.
- Legitimate interests — keeping the service secure and functioning correctly.
We do not rely on any legal basis for advertising, because we do not advertise.
How long data is kept
Your account and learning data are retained for as long as your account exists. When you delete your account, your account record and all associated learning data are deleted from our database, and your analytics profile is deleted from our analytics provider. Data held on your own device is removed when you delete the app.
Backups held by our hosting provider may retain deleted data for a short period before they expire in the normal course of backup rotation.
Your rights and how to exercise them
You can, at any time:
- Delete your account and all your data — in the app, go to Settings → Account → Delete Account. This is immediate and permanent; it cannot be undone.
- Turn off analytics — Settings → Privacy → Share usage data.
- Sign out, leaving your cloud data intact for a later sign-in.
- Request a copy of your data, or ask us to correct or restrict it, by emailing the address below.
If you are in the EU/EEA or UK, you also have the right to object to processing, the right to data portability, and the right to lodge a complaint with your national data protection authority. If you are a California resident: we do not sell or share personal information as those terms are defined by the CCPA/CPRA.
Deleting your account does not cancel an active subscription. Subscriptions are managed by Apple — cancel from Settings → [your name] → Subscriptions on your iPhone.
Children
Unlock Chinese is not directed to children under 13, and we do not knowingly collect personal data from them. If you believe a child has provided us with personal data, contact us and we will delete it. If a parent sets the app up on a child's device, the parent is responsible for the account and for the data associated with it.
Security
All network traffic is encrypted in transit. Your session credentials are stored in the iOS Keychain. Access to stored data is enforced per account at the database level, so one account cannot read another's data. No system is perfectly secure, but no payment details are ever held by us, which removes the most sensitive category of data entirely.
Changes to this policy
If this policy changes materially, the updated version will be posted here with a new "last updated" date, and — where the change is significant — you will be notified in the app.
Contact
Questions, requests or complaints about privacy: 888lucasliu@gmail.com