Memory Duel is a memory-matching duel game. This page explains, in plain terms, what information the app touches, why, and what choices you have — including when you play the online duel mode against other players.
To offer Online Duel — matchmaking, live matches, and the leaderboard — the app signs you in automatically and anonymously through Firebase Authentication. This creates a random identifier for your install; on its own it is not linked to a name, email address, phone number, or any other personal detail, and there is no password anywhere in the app.
From the Online Duel screen, you can optionally link your anonymous identifier to a Google account. If you do, we receive the name and email address on that Google account and store your name (not your email) alongside your identifier, so opponents and the leaderboard can show your real name instead of just your class. This is entirely optional — anonymous play works exactly the same either way — and it also means your progress can follow you if you reinstall the app or switch devices, instead of starting over. Google's own handling of your account information is described in the Google Privacy Policy.
While you use Online Duel, the following is sent to our Firebase backend so the match and leaderboard can work:
If you haven't signed in with Google, none of this is shown alongside anything that identifies you personally — other players only see your chosen class and your stats.
Solo play, progress, and preferences are stored locally in the app's own storage and never leave your device: currency earned, ladder progress, unlocked achievements, purchased upgrades, difficulty setting, and the sound/vibration/language settings. Uninstalling the app deletes all of it.
Memory Duel shows optional rewarded video ads (for example, a bonus after a win) through Google's AdMob. Showing an ad involves Google collecting device and advertising identifiers to select and measure ads; we don't receive or store that data ourselves. Google's own practices are described in the Google Privacy Policy and How Google uses information from sites or apps that use our services. You can watch these ads or simply skip that button — nothing in the app requires them.
We don't use your information for marketing, we don't build advertising profiles ourselves, and we don't sell it to anyone.
Online match and leaderboard data — and, if you choose to sign in, your Google account authentication — is processed by Firebase (Google) as our backend provider. Rewarded ads are served by Google AdMob. Neither is used for any purpose beyond running the game and showing the ads described above, and we don't share your information with any other third party.
Memory Duel doesn't use a signup form — if you've linked a Google account from the Online Duel screen, here's how to remove it and the data tied to it.
Email memoryduel@gmail.com from the Google address you signed in with (or tell us the display name shown in the app if you're not sure which one). Ask us to delete your Memory Duel account. We'll confirm by email once it's done — within 30 days of your request.
Memory Duel is not directed at children under 13, and we don't knowingly collect information from them beyond the anonymous, non-personal identifiers described above. If you believe a child has provided us information beyond that, contact us and we'll remove it.
Online data is protected by Firebase security rules that restrict each match and profile to the players involved in it. No method of transmission or storage is perfectly secure, but we take reasonable steps appropriate to the limited, non-personal data this app handles.
If this policy changes, we'll update the effective date above. Continued use of the app after a change means you accept the updated policy.