Draft. This text is awaiting legal review and may change.

Privacy policy

Effective from ⟨publication date⟩. Draft of 10 October 2026.

DaoLang is an app for learning Chinese words on iPhone and Android. This page says what data the app collects about you, why, where it is kept and how to delete it.

The data controller is ⟨developer's name⟩, ⟨country⟩. Contact: help@mozaika.app.

In short

• The app keeps your learning progress so that it is on all your phones and survives a reinstall.
• There are no ads. Your data is not sold or shared with ad networks. There is no tracking across apps.
• You can delete your account and everything tied to it in the app: "Settings → Delete account and progress".

What we collect

Account. You can learn without signing up: the app then creates an anonymous account tied to your phone. If you sign in with email, Google or Apple, we receive your email address and, if you share it, your name. Your password is kept by Firebase Authentication; we never see it.

Learning progress. Your answers and how well you remember each word; the lessons and units you have finished; your day streak and daily goal; gems and streak freezes; app settings (language, text size, typeface, mascot). Without these the app cannot decide what to review and when.

Leagues. If you join a weekly league, the members of your group see your name in the app, your mascot and your points for the week.

Questions to the AI helper. Only if you turn the helper on and agree: your question, the task it is about and your answer to that task. Anthropic (the Claude model) receives them to write a reply. You can withdraw consent in the settings.

Reports about tasks. If you report a task: the task itself, your comment, the app version and the platform. Reports are how the course gets fixed.

Crash reports (Firebase Crashlytics). If the app crashes or fails to save your progress: phone model, system and app version, where in the code it broke and a random installation identifier. No name, email or answers are in the report. You can turn sending off: "Settings → Send crash reports".

Notifications. If you allow notifications: the device's notification token, platform, app version, your language and time zone, so that a reminder arrives on time and in your language. When you sign out, the device record is deleted. You choose which notifications you get in Settings → Notifications.

App verification. Requests to the server carry proof that they come from the real app on a real phone (Firebase App Check: Play Integrity on Android, App Attest and DeviceCheck on iPhone).

What we do not collect. Contacts, photos, precise location, advertising identifiers. Voice recordings are not stored: pronunciation is checked by the phone's own speech recognition, and the sound is processed by Apple or Google under their own terms.

Why

• To make the app work: show your progress, decide what to review, keep your streak and leagues.
• To find and fix errors, from crash reports and reports about tasks.
• To answer your question to the helper, if you asked one.
• To protect the server from forged requests.

The legal basis is performing our agreement with you (the terms of use), and for the AI helper, your consent. ⟨Confirm with a lawyer the basis for crash reports and notifications under the controller's law.⟩

Who else receives data

• Google (Firebase): sign-in, data storage, server logic, crash reports, app verification, notifications. Data is kept in Google Cloud, ⟨Firebase project region⟩.
• Apple and Google: sign-in with their accounts, if you choose it; speech recognition.
• Anthropic: questions to the AI helper, only with your consent.
• jsDelivr: if the app downloads the strokes of a character it does not carry, the delivery network sees your device's address, as any website does.

Data is shared with no one else, except where the law requires it.

How long it is kept

Account data and progress: for as long as the account exists. An anonymous account that has not been opened for ⟨period⟩ may be deleted. Crash reports are kept for up to 90 days. Reports about tasks stay after an account is deleted, but no longer linked to it.

How to delete your data

In the app: "Settings → Delete account and progress". The server deletes your profile, progress, wallet, leagues, questions to the helper and the account itself. Details, and how to delete without the app: mozaika-35ab5.web.app/en/delete-account.

Your rights

You can find out what data we keep about you, correct it, delete it, withdraw consent to the AI helper and turn off crash reports. Write to help@mozaika.app. ⟨Confirm with a lawyer: the right to complain to a supervisory authority and the list of rights under the law of the controller's and the users' countries.⟩

Children

The app is not meant for children under ⟨13⟩, and we do not knowingly collect their data. If you find out that a child has created an account, write to us and we will delete it.

Changes

When this policy changes, the new version appears on this page with a new date. The app will tell you separately about significant changes.