Legal
Privacy Policy
CharGem — a children's Chinese-character learning app by Next Star AI
Effective date: 2026-07-10 · Last updated: 2026-07-10
The short version
- 🧒 Parents create the account and control everything.
- 📚 We collect only the minimum needed to learn: the parent's login, and each child's nickname and progress.
- 🚫 No ads, no third-party tracking, and we never sell data.
- 📴 Progress lives on your device; it only syncs to your account when you sign in.
- 🗑️ You can view, edit, or delete a child's data anytime.
1Who we are
CharGem ("the Service") is operated by Next Star AI ("we", "us"). For any privacy question, email support@nextstarai.com.
2What we collect
| Data | Source | Purpose |
|---|---|---|
| Parent email + password, or Google sign-in (name, email) | Parent | Create/secure the account, sync across devices |
| Child's display name (nickname), avatar, colour | Parent enters | Tell each child's profile apart |
| Learning progress: characters practised, mastery, gems, streaks, XP | Created by use | Power spaced-repetition & the progress report |
| Settings: script/reading/language preferences | User | Remember your choices |
We do not collect a child's real full name (a nickname is enough), address, phone, birthday, photos, precise location, or contacts, and we do not use the camera or microphone. Pronunciation uses your device's built-in speech synthesis — nothing is recorded or uploaded.
3Children's privacy & parental consent
The Service is designed for children and we treat children's privacy with care (consistent with the U.S. COPPA, EU GDPR-Kids, and Taiwan's PDPA). Accounts are created only by a parent or guardian. By creating an account and adding a child profile, the parent consents to our processing of the minimal data above under this policy. We do not show children advertising and do not ask children for personal information beyond what learning requires. Parents can review, correct, or delete a child's data at any time (see §7).
4How we use data
- To provide and personalise learning (review scheduling, grade-adaptive difficulty, progress & gems).
- To sync progress across your devices when you sign in.
- To keep the account secure, prevent abuse, and fix problems.
We do not use data for behavioural advertising or build ad profiles from a child's activity.
5Storage & service providers
Progress is stored by default in your device's local storage. If you choose to sign in, it syncs to our self-hosted server, restricted by per-user permissions so only your account can access it. We share data with the providers below only as needed to run the Service. We do not sell personal data or share it for others' marketing.
| Provider | Role |
|---|---|
| Our self-hosted backend server | Account & progress sync |
| Google (only if you use Google sign-in) | Parent authentication |
| Our hosting provider | Hosting; standard server logs (e.g. IP) |
| Content delivery & fonts | Serve stroke data & fonts (no personal data) |
Friends (optional): if a child adds friends, only their nickname, avatar, gem count, streak and level are shared with those friends — never a real name, contact details, or location. Kids connect only by exchanging a friend code (there is no search or discovery), and can only send preset cheers/emojis — never free-text messages. You can remove a friend from the friends list at any time.
6Cookies & tracking
We use only a necessary first-party cookie to keep the parent signed in. We use no advertising cookies, third-party analytics, or cross-site tracking.
To understand whether the app works well, we record anonymous first-party usage counts (for example, "app opened" or "a practice was completed"). These records contain only a random device code and a date — never a child's name, any study content, or personally identifying data — and are not shared with any third party.
7Your rights & choices
- Access & edit: change a child's name/avatar anytime in ⚙️ Settings, or view progress in the Parent report.
- Delete: deleting a child profile erases their progress; "Reset progress" clears one child's records; signing out and deleting the account removes cloud data.
- Opt out of sync: use the app fully offline without signing in — data stays on the device only.
- You may also email support@nextstarai.com to access or delete your personal data. Under GDPR/PDPA you also have rights to rectification, restriction, and portability.
8Retention & security
We keep data only while the Service is in use; deleting a profile or account removes the associated data. Traffic is encrypted with HTTPS and cloud data is isolated by per-user permissions. No online service can be 100% secure, however.
9International users
Families may use the Service from Taiwan, the U.S., and elsewhere. By using it, you understand data may be processed in the regions where we and our providers operate. We handle data consistent with COPPA, the GDPR (including its children's provisions), and Taiwan's PDPA.
10Changes
If this policy changes materially (for example, if analytics is added in future), we'll update the date here and notify you in the app. Continued use means you accept the updated policy.