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Privacy Policy: Android
Math Express (cz.mathexpress) for Android Developer: Jan Bílek Effective 9 September 2026
This game collects no personal data. It does not connect to the internet, sends nothing from the phone, and contains no ads, no purchases and no tracking.
Three things, in the app's private storage on the phone:
settings — school year, chosen arithmetic operations, time per sum, language, station colours, and sound and music volume; high scores — points, trains delivered, success rate in percent and the date the game was played; the list of special events the player has already encountered. None of this contains a name, an e-mail address, a location or any device or personal identifier. It lives in the app's private storage, which other apps cannot reach, and the game never sends it anywhere.
it does not connect to the internet — the app declares no permissions at all, network access included; it collects and transmits no data about the player or the device; it shows no ads and contains no in-app purchases; it uses no analytics and no third-party libraries; it requires no account and no sign-in; it does not access contacts, photos, files, location, microphone or camera. Children The game is made for children, which is precisely why it collects nothing at all. No data is gathered from children or adults, so there is nothing to pass on, nothing to lose and nothing to misuse. There are no ads, no purchases, no chat and no links leading outside the app.
The only way stored data can leave the phone is outside the game: Android may include the settings and high scores in the system backup held in the phone owner's Google account, so the game continues where it left off on a new device. This is governed by the phone's settings, not by the app, and the developer has no access to such a backup. Backup can be switched off in Android settings.
Uninstalling the game removes all stored data from the phone. So does "Clear data" in the system app settings.
Any changes to this policy will appear on this page together with a new effective date.