Privacy Policy

Brilliant Chess · Last updated: 4 July 2026

This Privacy Policy explains what personal data the Brilliant Chess mobile app and its backend (“Brilliant Chess”, “we”, “us”) collect, why we collect it, who we share it with, how long we keep it, and the choices you have — including how to delete your account and data.

1. Data we collect

Account & sign-in

You can sign in with any one of three methods. We only collect what that method provides:

Google Sign-In — your Google account identifier and the email/display name Google returns, used to create and recognise your account.
Email one-time code (OTP) — your email address, used to send the sign-in code and to identify your account.
Telegram Mini App — your Telegram user id, used to auto-sign-in inside Telegram.

Every account has a display name (shown to other players) and an in-app username. We do not ask for or store a password for normal players.

Gameplay

Your ratings (bullet, blitz, rapid) and win/loss/draw statistics.
Your game history — opponents, results, time controls, timestamps, and the moves played.
In-game chat messages you send, and reports you file about other players.
Your friends list and friend requests.

Technical & security

IP address — processed server-side to rate-limit abusive traffic and protect the service. It is not part of your public profile.
Push-notification token — if you enable notifications, we store a Firebase Cloud Messaging (FCM) device token so we can send you game and friend notifications. It is removed when you sign out on that device or delete your account.

Diagnostics & analytics (via Firebase)

Crash & ANR diagnostics (Firebase Crashlytics) — crash stack traces, app-not- responding events and device/OS metadata, so we can fix stability problems.
Analytics (Firebase Analytics), including your device’s Advertising ID — aggregate usage events that help us understand which features are used and improve the app.

2. Why we use your data (purposes)

Purpose	Data used
Create and secure your account, sign you in	Google id / email / Telegram id, display name, username
Match you, run games, maintain ratings & history	Gameplay data, display name
Social features (friends, chat, reports)	Friends, chat messages, reports
Prevent abuse & keep the service reliable	IP address
Diagnose crashes and improve the app	Crash/ANR diagnostics, analytics, Advertising ID

3. Who we share data with (third parties)

We do not sell your personal data. We share data with the service providers we rely on:

Google / Firebase — Google Sign-In (authentication), Firebase Crashlytics (crash & ANR reporting) and Firebase Analytics (usage analytics, Advertising ID). Their handling of this data is governed by Google’s Privacy Policy.
Telegram — only if you choose to sign in through the Telegram Mini App.

We may also disclose data where required by law.

4. How long we keep it (retention)

Account & gameplay data — kept while your account exists. When you delete your account, your identifying data is erased (see below).
Game records — after deletion, past games are retained for your opponents’ history with your player reference anonymised to “Deleted user”. They no longer identify you.
Sign-in codes & IP-based rate-limit state — held only transiently (minutes) and then discarded.
Crash & analytics data — retained by Firebase according to Google’s retention settings.

5. Your right to delete your account and data

You can delete your account and personal data at any time:

In the app: Settings → Delete account.
On the web: use our account deletion form if you no longer have the app installed.

When you delete your account, we permanently remove it from our systems. Specifically, we:

erase your email, display name and username;
delete your linked sign-in identity — including the Google / Firebase Authentication account and the Telegram identifier connected to you — so that sign-in is removed from Firebase Authentication and no longer appears there;
remove your registered push-notification (FCM) device tokens, so your devices stop receiving notifications from us;
delete your friends, friend requests, challenges, activity feed, reports and in-game chat messages;
sign you out on all devices.

Past games are kept for your opponents’ history with your player reference anonymised to “Deleted user”; they no longer identify you. Crash and analytics data already sent to Firebase is retained by Google under its own retention settings.

6. Children

Brilliant Chess is not directed to children under the age required by your country’s law. We do not knowingly collect data from them.

7. Changes to this policy

We may update this policy. Material changes will be reflected by the “Last updated” date at the top of this page.

8. Contact

Questions or data requests: m1nexsupport@gmail.com.