Last updated: 23 July 2026 · Applies to the StarTrails web app and Android app
StarTrails is an offline educational learning game for children by Opzeker IT (Netherlands). This policy explains what data the app uses, why, and what your rights are.
| Data | Why | Leaves this device? |
|---|---|---|
| A self-chosen player name (free text, max. 14 characters) | Shown on the profile so a child can pick their own character | No — never sent anywhere |
| School grade (2–6) and app language | Adjusts question difficulty and on-screen/spoken language | No |
| Avatar choices (animal, colours, hair, eye colour, pattern, star-tail) | Cosmetic character customization | No |
| Game progress (stars per level/world/subject, unlocked items) | Tracks learning progress across sessions | No |
A real name, email address, photo, or any other identifying information is never requested. There is no login or account system.
Data is stored only locally on the device, in the
browser's localStorage (or the Android WebView's equivalent
inside the app). StarTrails has no server, no database and no cloud
storage of any kind, so it is technically impossible for us to receive,
see, or store this data anywhere else. Multiple profiles on one device
(e.g. siblings) are kept side by side, each with their own data.
Questions are read aloud for young players using on-device text-to-speech
(Android's native TextToSpeech, or the browser's
speechSynthesis in the web version) — this audio is generated
and stays on the device; StarTrails never records, receives or processes it.
One exception, in the web version only: opening StarTrails in a regular browser (not the Android app) loads the "Fredoka" and "Nunito" fonts from Google Fonts, which can expose your IP address to Google as with any visit to a Google service. The Android app makes no network connections at all and uses the device's own system fonts instead.
Data stays on the device for as long as you don't clear it. You can delete a single profile or reset its progress at any time from inside the app, or erase everything at once by clearing the site's storage in your browser or uninstalling the Android app.
Because all data stays on your own device, you are always in full control of it without needing to ask us: open "Edit profile" → "Delete profile" to remove one profile, or "Edit profile" → "Reset progress" to keep the profile but clear its stars and unlocked items. To erase everything at once, clear this site's data in your browser, or clear StarTrails's storage (or uninstall the app) via your Android device's app settings.
StarTrails is designed for children (primary-school grades 2 through 6, roughly ages 5–12) and is built specifically so that no personal data ever leaves the device: no collection, no profiling, no targeted advertising, and no chat, messaging or contact with other players or strangers. Parents and teachers can use the app together with a child without concern; there is no separate parent account because nothing is tracked outside the device to begin with.
If this policy changes materially — for example, if a future version ever adds functionality that sends data off the device, which is not the case today — we will update this page and note the date above.
Opzeker IT — startrails@opzeker.it — opzeker.it