Last updated: 31 October 2026
Bridge Engineering: The Master is a game made by Kode4u ("we"). This policy explains what information the game uses, why, and what you can do about it. It covers the Bridge Engineering apps for Android and iOS and the Bridge Engineering game server at bridge.kode4u.tech.
Information stored on your device
Your progress stays on your phone: unlocked levels, stars, saved bridge designs, your own load-test records, daily-challenge streak and settings. It is not sent to us. Uninstalling the app deletes it.
Information used for online features
The World ranking, the bridge leaderboards, the Daily Challenge board and online multiplayer (Load-off) use the following:
| What | Why | Who can see it |
|---|---|---|
| A random player ID created by Google Firebase Authentication (anonymous sign-in, no account or password) | So your profile and scores stay yours on this device | Only us and Google, who host it |
| The player name you choose | Shown next to your rank and results | Other players |
| Your star totals and rank title, and when they were last updated | The World ranking | Other players |
| Bridges you submit ("Go global", Daily Challenge, multiplayer): the design, its cost and the load it carried | Our server re-runs the load test to verify the result, then records your best result per bridge on the leaderboard | Everyone who views that leaderboard |
| A random device ID created by the app | To recognise you in a multiplayer room and limit spam | Only our server |
| Your IP address | Needed to connect; used briefly to stop abuse and kept in our web server's logs for up to 30 days | Only us |
Profiles and leaderboards are stored in Google Cloud Firestore (part of Firebase). Google processes this data for us under the Firebase privacy and security terms. Please don't use your full real name or anything private as your player name: other players can see it.
Advertising (Google AdMob)
The apps are free and may show a full-screen ad between levels (never during a simulation, never in multiplayer, and never in your first levels). The ads come from Google AdMob. To show, measure and limit ads and to prevent fraud, Google may collect your device's advertising ID, your approximate location (from your IP address), device and app information, and how you interact with ads. Google handles this under its own policy: How Google uses information from sites or apps that use its services. We don't receive this information ourselves.
Your choices. In the European Economic Area, the UK and Switzerland, the app asks for your consent first, and you can change your choice at any time with Settings › Privacy options (ads). Anywhere, you can reset or delete your advertising ID, or opt out of personalized ads, in your phone's settings (Android: Settings › Privacy › Ads; iPhone: Settings › Privacy & Security › Tracking and Apple Advertising).
What we don't do
- No analytics of our own, and we don't track you across other companies' apps or websites (the AdMob section explains what Google does to show ads).
- No access to your contacts, precise location, camera, microphone or files.
- No in-app purchases.
- We never sell or rent your information, and we don't share it except as described here or when the law requires it.
How long we keep it
We keep your profile and leaderboard results while you play, so they are still there when you come back. Multiplayer rooms are kept in memory only for the match. Web server logs are deleted after 30 days.
Delete your data
In the game, open Settings › Delete my online data. This deletes your profile, all your leaderboard results and your anonymous sign-in immediately. You can also ask us by email at info.kode4u@gmail.com (see how to delete your data); we delete it within 30 days. To delete the progress stored on your device, uninstall the app or clear its data.
Children
Bridge Engineering is an engineering game for teenagers, students and adults. It is not directed at children under 13 and we don't knowingly collect personal information from them. If you believe a child has given us personal information, contact us and we will delete it.
Security
The app talks to Firebase and to our server over encrypted connections (HTTPS / secure WebSocket). Leaderboards can only be written by our server after it has verified a result, and each player can only change their own profile.
Changes
If we change this policy, we'll update this page and the date at the top. Big changes will also be announced in the game.
Contact
Questions about privacy? Email Kode4u at info.kode4u@gmail.com.