What Hanzi Genz collects, why, who receives it, how long we keep it, and how you stay in control.
Version 4.0 · Effective: 26/10/2026
This is an English translation provided for your convenience. Hanzi Genz operates under Vietnamese law, and the Vietnamese version is the legally binding one.
| Data | Purpose | Kept for |
|---|---|---|
| Account: email, name and profile photo (via Google) or email + hashed password; the age group you choose (no date of birth). | Sign-in, syncing across devices. | Until you delete your account (fully removed after 30 days). |
| Study progress: words learned, review schedule, practice and mock-test results, goals and self-reported level, notes, settings. | Providing the study service. | Until you delete your account. |
| Payments: order code, plan, amount, date; buyer name and email sent with the order. No card details are stored. | Payment, plan activation, refunds, tax duties. | 5 years as required for tax. AI Credit ledger: 1 year. |
| AI and voice: text you send to AI and the clip recorded when you press record. Recordings are sent only after you agree. | Answers, writing feedback, pronunciation scoring, speech-to-text. | Not stored on our servers: discarded after processing. The server only logs usage (feature, credits), not the content. |
| Community: name or nickname, photo, study days and score on the leaderboard; what you post in the Tea Lounge, shared decks and study rooms (public); who was matched with whom in Pair Chat (messages are not stored); invite codes and hashed IPs for referrals. | Running community features, preventing fake accounts and abuse. | Until you remove it, leave the board or delete your account. |
| Feedback and lookups: feedback you send; searches with no result while signed in (strings that look like emails or phone numbers are dropped). | Fixing and adding content. | Until you delete your account. |
| Technical: IP, browser, device, error logs, feature usage; push address if you turn on review reminders; consent log. | Operations, security, bug fixing, improving the app; proving consent. | Logs: 90 days. Push: until you turn it off. Consent log: 5 years. |
Your email is never shown anywhere. The leaderboard shows your Google name and photo; you can switch to a nickname or leave the board at any time.
| Recipient | What for · which data | Location |
|---|---|---|
| Supabase | Database, sign-in — all app data | United States |
| Cloudflare | Page delivery, audio and image storage | Global |
| PayOS | Payments — name, email, order code, amount | Vietnam |
| Google sign-in; embedded YouTube videos; fonts — IP and browser when these load | United States | |
| Your browser's maker (Google, Microsoft…) | Quick check — what you read aloud, sent by the browser, only if you agree; the app never receives that audio | Per vendor |
| DeepInfra, fallback DeepSeek | Running AI models — text you send to AI | United States · China |
| Anthropic | In-depth scoring of writing and HSKK speaking when you choose it — task and answer | United States |
| Microsoft Azure Speech | Pronunciation scoring — voice clip and model sentence | Hong Kong |
| Groq, DeepInfra | Speech-to-text — voice clip | United States |
| Music services you connect | The player loads only when you open it; that service receives IP and browser under its own policy | Per service |
Internally, only the business owner and authorised operators can access data, when needed for support, bug fixing or at the request of a competent authority. Your data is therefore stored or processed outside Vietnam in the locations listed. We choose partners with security commitments and send only the data their job needs.
You have the right to be informed, to give or withdraw consent, to access, correct, delete, restrict or object to processing, to receive a copy of your data, and to complain, denounce or sue under the law. Most of this works directly in Me › Settings (edit, "Export my data", "Delete account", Privacy); anything else goes to the contact below.
You must provide truthful information, protect your account and respect other people's data (do not post other people's personal information publicly).
Personal-data contact: [email protected] (subject "DATA REQUEST"). We acknowledge receipt within 2 working days and handle the request within the legal deadline. Complaints about data security go to the same address and follow the same timeline; if you disagree with the outcome, you can complain to the competent authority.
The app is for people aged 16 and over; ages 13–15 need a parent's or guardian's consent; it is not for children under 13. Pair Chat is only for people aged 18 and over. Parents can email the contact in section 4 to have their child's account deleted.
Encrypted connections (HTTPS), hashed passwords, and each person can access only their own data. If a data breach happens, we handle it and notify the competent authority and affected people within the legal deadline.
Each version has a number and an effective date; important changes are announced in the app. Before using data for a new purpose, we ask for your consent.
HANZIGENZ household business — code 001206035506 · No. 29, Thong Nhat hamlet, Phu Xuyen commune, Hanoi · responsible person: Nguyễn Tuấn Trường · phone 0889952456 · [email protected]. Support: [email protected].