Sudoku Hurdle Privacy Policy

You can play Sudoku Hurdle without giving us your name, your email, or anything else about you. The game creates an anonymous identifier on your device the first time you open it, and that identifier — not you — is what your puzzles, coins and purchases are attached to.

One thing is worth knowing before you read the rest: if you choose a leaderboard name, that name and your solve times are public to anyone, whether or not they use the app. Deleting your account takes them down along with everything else — section 10 sets out exactly what goes and the one thing that stays.

On first launch the app obtains an identifier and stores it on your device. Everything the game records is attached to that identifier. It is not derived from your name, your email, your phone number, your advertising ID or your hardware.

If you never sign in, that identifier is all we have — there is no account, and no way for us to connect it to a person. If you do sign in, the same identifier is upgraded in place and your email address becomes attached to it.

Attached to that identifier, the server keeps:

• Daily puzzles — which day you played, how long the solve took, the moves you made, and how many hints you used.
• Classic puzzles — the difficulty, which puzzle it was, how long it took, and how many moves.
• Coins — a running ledger of every coin earned and spent, including what each spend was for (a hint on a particular puzzle, a past day you unlocked).
• Monthly trophies and unlocked archive days.
• Your timezone offset— a number of minutes from UTC, declared by your device and then fixed, so that “today’s puzzle” means the same thing every day. It is a timezone band, not a location.
• A leaderboard name, if you set one. See section 3.

If you set a leaderboard name, that name and your solve times are readable by anyone on the internet. The leaderboard is served without any sign-in requirement, so it is not limited to people who have the app installed.

Choose a name you are comfortable being public. It is the only field you enter that we publish, and it does not have to resemble your real name.

Unless you subscribe to Plus, the game shows ads through Google AdMob: a banner while you play, an interstitial after every third puzzle, and optional rewarded videos you choose to watch in exchange for coins.

On iOS the app asks Google’s consent form first, and then asks for permission to track via Apple’s App Tracking Transparency prompt. The app requests personalised ads, and your answers to those two prompts are what Google uses to decide whether the ads you see are personalised. Declining does not change the game in any way — you will still see ads, they will simply be less targeted.

Google receives standard advertising signals directly from its SDK on your device; we do not see them and do not control them. When you watch a rewarded video, and only then, the app passes your Sudoku Hurdle identifier to Google so that Google can confirm back to our server that the video really was watched and the coins are owed. Banner and interstitial ads carry no such identifier.

The app also declares Apple’s SKAdNetwork identifiers, an Apple mechanism that reports app installs to advertisers without identifying you.

The app sends crash and error reports to Sentry so that faults can be found and fixed. Reports carry the stack trace, a trail of what the app was doing, and basic device context such as the model, the OS version and the app version.

They are configured not to attach personal information: no IP address is recorded with the report, and no email address, account identifier or leaderboard name is attached to it. Anything after a ? in a URL is stripped before the report leaves your device. When a puzzle fails to submit, the report also carries the mode, the difficulty, the move count and the error code — nothing about you.

If you allow notifications, the app registers your device’s push token with Sendora Cloud, along with the platform and the app’s bundle identifier, so a reminder can be delivered to it. If you tap a notification, the app reports which message it was, so we can tell whether the reminders are worth sending.

You can turn notifications off at any time in your device settings.

Coins and Plus are bought through Apple. We never see your card, your billing address or your Apple ID. Apple tells our server that a purchase happened, and we record the transaction identifier, what was bought, whether it was a live or a test purchase, and the identifier it belongs to — so the coins reach the right player and a refund can be honoured.

Apple also notifies our server about renewals, cancellations, refunds and billing problems for a subscription. Those notices are recorded so that Plus turns off when it should.

Our server does not store your IP address, your user agent, or any device fingerprint. It reads no request headers other than the one carrying your sign-in token, and there is no request log.

For completeness: our API sits behind Cloudflare, which terminates the connection and therefore sees the IP address of every request, as any network provider between you and us would. Nothing in our own systems keeps it.

There is no Firebase Analytics, Amplitude, Mixpanel, Facebook SDK or AppsFlyer in this app. Sentry runs only on your device’s copy of the app, never on our server. Our database is one we run ourselves, not a hosted service belonging to somebody else.

• Google AdMob — serves the ads, and confirms rewarded videos. See section 4.
• Apple — takes the payment and tells us the outcome. See section 7.
• Sendora Cloud — handles sign-in and delivers notifications. If you sign in with an email address or with Apple, your account lives there.
• Sentry — receives crash reports from the app. See section 5.
• Cloudflare — carries traffic between your device and our server, and serves this website.

We want to be exact about this, because it is the part most policies are vague about.

Deleting your account from inside the app removes your sign-in account and then erases the game records held against your identifier: your daily and Classic puzzle history, your coin ledger, your trophies, your unlocked archive days, your subscription record, and your leaderboard entry, which disappears from the public board.

One thing is kept, and it is not about you. A receipt for a purchase — the store’s transaction number and what it was for — stays, with your identifier and account token stripped off it, so that it belongs to nobody. That is what lets a refund be matched to a payment months later, and stops the same transaction being credited twice to whoever holds that store account next. It cannot be traced back to you: the identifier is gone and so is the account row it pointed at.

If your sign-in provider gives you a grace period, deletion is not immediate: signing back in during that window cancels the whole thing, and nothing has been erased yet when it does. Once the window passes without you returning, the erasure runs. The app tells you which of the two happened when you delete.

Game records are otherwise kept for as long as the game runs; there is no automatic expiry. To ask what we hold about you, or for a copy, email [email protected].

Sudoku Hurdle is not directed at children under 13, and we do not knowingly collect information from them. If you believe a child has given us information, write to the address below and we will remove it.

If this policy changes in a way that affects what we collect or who we share it with, the date at the top changes and the new version is published here before the change takes effect in the app.

For privacy questions, data requests, deletion requests, or complaints, email [email protected].