Privacy Policy

ChessPeak · Last updated 2026-11-09

ChessPeak is a chess training and play app. This page explains what information the app collects, why, who can see it, and how you can remove it. The app has no ads, and we do not sell or share your data for advertising.

Training without an account: stays on your device

If you only use the puzzle trainer, Puzzle Rush, Woodpecker sets, bots, openings, endgames, lessons or game review, and you never sign in or play a friend, no account is created and nothing you do is sent to us. Your progress, ratings and settings are stored only in your browser's local storage on your own device. Uninstalling the app or clearing site data deletes them permanently; we cannot recover them. Share pictures you create are drawn on your phone and are not uploaded by the app.

Playing a friend online

When you open "Play a Friend", the app creates an anonymous guest account so your games can be saved and delivered to your friend in real time. We store:

• A random account ID with no personal information attached.
• The display name you chose for the game, and a username if you set one.
• The moves, clock and result of games you play, how long each move took (measured by our server), and your friend rating.
• Friend requests and the list of friends and blocked players.

Saving an email account

If you add an email and password so you can keep your account across devices, we also store:

• Your email address and an encrypted password (we never see or store the plain password).
• A synced copy of your training progress: puzzle stats and rating, streaks, achievements, study progress, game history and settings, so you can restore it on another device.
• Your daily plan reminder settings (on or off, the hour, your time zone, and the last day you trained).

You can also sign in with Google instead of a password. Google shares your email address (and the basic profile details Google provides) with our sign-in provider; the app uses only the email address, not your Google photo or name.

Your profile, photo and what other players see

Your profile is your username and an avatar: initials, a preset picture, or a photo you choose to upload. Other signed-in players can see your username and avatar when they play you, are your friend, or see you on a leaderboard. There is no public browsing or search of profiles. You can report another player's photo or username, and block players; reports are stored so we can review them, and a photo or name can be hidden or changed after several reports.

A signed-in player can open another player's profile sheet from a list, a leaderboard or a game. It shows the username and avatar, the month they joined, the chess rating and the record of their rated games, the puzzle rating, the puzzles solved this week, the best Puzzle Rush scores, and the head-to-head record of the games between the two of you. A friend's profile is always available to that friend; anyone else's only while they have "Show me on public leaderboards" switched on, and never if either of you has blocked the other.

Leaderboards and friends activity

• With a saved email account, your username, avatar and best Puzzle Rush scores can appear on the Puzzle Rush leaderboard, and your username, avatar and number of puzzles solved this week can appear on the weekly puzzle leaderboard. You can turn this off any time in Settings ("Show me on public leaderboards"), which covers both the Puzzle Rush and the weekly leaderboards. Guest accounts never appear on leaderboards.
• Your friends can see when you reach a streak or rating milestone, or win last week's leaderboard among your friends, in the friends activity list. Only a fixed set of milestone numbers is shared, never your puzzles or games, and entries older than 30 days are not shown. You can switch this off in Settings. Guests do not share activity.
• Puzzle Rush duels: when you challenge a player by username, or are challenged, we store the two account IDs, the list of puzzles, and each player's start time and score. Your opponent sees your score once they have played their own run. A player who switched off the public leaderboards only takes duels from friends, and guests cannot start duels. Duels are removed automatically after 30 days.
• The weekly league (Bronze to Diamond) is worked out from the weekly puzzle totals of you and your friends; it stores nothing more.

Tester sign-up (website)

The ChessPeak website has an optional form to ask for an invite to the Android test. If you type your email address there, we store it (with the app name and the date) only so the developer can add you to the Google Play test and write to you about it. It is kept in a separate table that the app cannot read, is not used for advertising, and is never sold or shared. To have it removed, write to the contact address at the bottom of this page and say which address.

Notifications

If you turn on notifications, we store a device subscription token, used only to deliver alerts you have chosen (for example "it's your move", friend requests, or the daily plan reminder). Alerts are listed in the in-app notification centre and removed after 30 days. You can switch each kind of alert to push, silent or off in Settings. The daily plan reminder is on by default, is sent at most once a day, and only if you have not trained that day. You can turn it off any time.

Fair play and rated games

Rated games need a saved email account. Casual games are open to everyone, with or without an account. To keep rated games fair we check every finished rated game automatically: a program replays every move to make sure the moves and the result are real, and a chess engine analyses the moves to estimate how closely play matches a computer. We store the results of that analysis for each game together with your account ID: how often your moves matched the engine's best choice, how much they differed from it, and how long each move took.

Only the developer can see these results. They are never shown to other players, and nothing happens automatically because of them: the developer reviews them and may remove an account that tampers with the app or cheats. Removing an account blocks its sign-in, and a record of the removal (the account ID and email address) is kept so the same email address cannot be used to sign up again. The analysis results are deleted when you delete your account.

Connecting a chess site (optional)

"Puzzles from your games" and "Play online" are optional. If you use them, your phone talks to Chess.com or Lichess directly; ChessPeak's servers are not in between and keep none of it.

• Puzzles from your games: you type your username on that site. Your phone asks the site for your public games, checks them on the phone, and keeps the username and the puzzles it made on the phone only.
• Play online: you log in on the Lichess page (we never see the password) and allow ChessPeak to play games for you. The login token stays on your phone, is not part of the backup file, and can be removed with Disconnect in the app or in your Lichess account settings. Your moves go from your phone to Lichess; the games are stored by Lichess under its own policy.

Premium subscription (optional)

ChessPeak Premium is an optional monthly or yearly subscription, bought through Google Play inside the Android app or with a card on the website. Google (in the app) or Stripe (on the website) handles the payment: ChessPeak never sees your card or payment details. Premium adds looks, badges, frames, extra streak freezes and removes the daily limits on a few tools.

• After you buy, your phone sends the purchase token from Google Play to our server, which checks it with Google. We keep: your account, which plan you have, whether it is active, the start and end dates, and a one-way scrambled copy (hash) of the purchase token. We do not keep the token itself.
• About once a day our server asks Google which purchases were refunded or cancelled and ends Premium for those. It compares the scrambled copies only; no personal details are exchanged.
• Website payments: Stripe, Inc. processes the card payment and sends us back the Stripe customer ID, the subscription ID, the plan and its start and end dates. We keep those so Premium can be switched on and off and so you can open the billing page from the app (Manage subscription). Your email address is passed to Stripe so it can send receipts. The full terms and refund rules are on the terms page. Stripe handles the data under its own privacy policy.
• To cancel, use Manage subscription in the app if you paid on the website, or Payments and subscriptions in Google Play if you bought in the Android app. Deleting your ChessPeak account removes our record of your Premium but does not cancel the subscription: cancel it first.

Weekly email (optional)

If you switch it on, ChessPeak sends one email a week to the address on your account. It contains the number of puzzles you solved last week, your puzzle rating and a link to the daily puzzle. It is off unless you turn it on (in Settings > Alerts, or when the app offers it once after your tenth puzzle), and only accounts with a saved email address can get it.

• Every email has an unsubscribe link that works in one click, and you can also turn it off in the app at any time.
• We keep one small record per player: whether the weekly email is on, when you changed it, and when the last one was sent. It is deleted with your account.
• The emails are delivered by Resend (resend.com), which receives your email address and the text of the email in order to send it. The emails contain no images and no tracking pixels, so we do not learn whether you opened them.

Sending feedback

The Feedback button in the app opens a Google Form in your phone's browser. The app itself sends nothing. What you type in the form goes to Google Forms and to the developer, and is handled under Google's privacy policy. Please do not put passwords or other private details in it.

Who can see your data

Only you and the players described above can see the data they are shown in the app. Game moves and results are visible to you and the friend you played. Our infrastructure providers, Supabase (database and sign-in) and Vercel (app hosting and notifications), process the data to run the app; they do not use it for their own purposes.

Our sign-in provider records the IP address and browser type of each sign-in. We use this to keep the service secure and, in the developer's own private statistics, to count one phone once instead of once per reinstall. The statistics never show IP addresses, and this information is not shared or used for advertising.

The developer can access the stored account data for support, fixing problems and keeping players safe (for example handling reports). We do not use it for anything else.

The developer can also see simple usage counts (which features are used and on which days), page-view counts from Vercel Web Analytics (which pages were opened, from which country and device type; no cookies and no account details) and error reports (the error, the screen and the app version) to fix problems. They contain no puzzle answers, moves or messages, and the counts tied to your account are removed when you delete it.

Deleting your data

In the app: sign in, open Settings and choose "Delete my account" under Danger zone. This permanently removes your profile, photo, friends, synced progress, rating, leaderboard scores, Puzzle Rush duels, activity, reminders, notifications, fair-play analysis, your Premium record, usage counts and your sign-in. Finished games stay in the other player's game history with your name replaced by "Deleted player" and no link to an account; a game still in progress ends as a win for the other player.

By email: write to the address below from the email on the account and we will delete it. More steps are on the delete your account page.

Deleted data is removed from our live database immediately. Backups kept by our database provider can hold a copy for a short time before they are overwritten. Training data stored only on your device is removed by clearing the app's data or uninstalling it.

Children

This app is not directed at children under 13, and we do not knowingly collect data from them.

Changes

If this policy changes, the "Last updated" date above will change.

Contact

Questions about this policy or your data: clevercornergames@gmail.com