Privacy policy

Playing without an account

Games against the computer, games with a friend on the same device, the lessons and the About pages work without an account and without sending any personal information to us.

To work this way, the game keeps some things in your browser’s storage on your device: your settings (theme, speed, sound, board layout), a game in progress so you can resume it, and copies of pages so the game works offline. A cookie may remember your language. This stays on your device; you can remove it at any time by clearing the site’s data in your browser.

We don’t use advertising, analytics or tracking cookies. If that ever changes, we will update this policy first.

Playing online

When online play is available and you choose to use it, we process:

• Account details: a guest account is identified only by a random ID. If you create or save an account, we also keep your email address; your password is stored only in hashed form by our sign-in provider.
• Your profile: username, display name and the avatar you pick.
• Your games: every move with its time, the result, and whether a move was played for you when time ran out.
• Ratings and record: your rating and win, loss and draw counts for each game type.
• While you play: whether you are connected (so your opponent sees you are online) and the reactions you send. These are passed to your opponent in real time and are not stored.
• Technical data: your IP address and device information are handled by our providers to deliver the service, keep it secure and limit abuse (for example, how many accounts can be created from one address).

Why we use it

We do this because it is needed to provide the online game you asked to use, and in our legitimate interest in keeping it fair and secure. We never sell your information.

• To run online games: match you with opponents, check that moves follow the rules, enforce move timers and record results.
• To keep ratings and the leaderboard.
• To sign you in and send the emails you ask for, such as sign-in links.
• To protect the service and its players from cheating and abuse.

What other players can see

Your email address is never shown to other players.

• Your username, display name and avatar, in games, on the leaderboard and on your profile page.
• Your ratings and win, loss and draw record.
• Finished and abandoned games: anyone can replay their moves and see the result, including from your profile.

Who processes data for us

We use a small number of providers that act on our instructions: Vercel hosts the website, Supabase runs the accounts, database and real-time connections, and an email service delivers sign-in emails. These providers may store data in other countries than yours; we rely on their contractual safeguards for such transfers.

How long we keep data

• Accounts are kept until you ask us to delete them. Unused guest accounts may be removed after a period of inactivity.
• Games and ratings are kept while the account exists, so ratings and replays stay accurate. When an account is deleted, its profile and ratings are deleted; games it played may be kept without the name, so the other player’s history stays intact.
• Provider logs are kept for a limited time for security and troubleshooting.

Your choices and rights

You can change your username, display name and avatar in the app, and you can play without an account at all. You can ask us for a copy of your information, to correct it, or to delete your account; depending on where you live you may have further rights, including to object to processing or to complain to a data protection authority.

Children

Offline play collects nothing and is suitable for everyone. Online accounts are for people aged 13 or over, or the minimum age for such services where you live if higher. If you believe a child has created an account, contact us and we will delete it.

Security

Connections to the game are encrypted, access to data is restricted so players can only change their own games and profile, and passwords are never stored in readable form. No system is perfectly secure, so please use a password you don’t use elsewhere.

Changes to this policy

If we change this policy, we will update the date below and, for significant changes, tell you in the app.

Contact

A contact address for questions and data requests will be published here.