Privacy Policy for Sudoku: Classic Number Puzzle

This policy describes how Sudoku: Classic Number Puzzle ("the App"), published by PlayBrain, handles information. The App is a single-player offline puzzle game with no account and no online play.

The short version

• No account, sign-in, name, email, or any personal detail is needed to play, or accepted.
• Your puzzles and progress are saved only on your device and are never uploaded.
• Two things leave your device: anonymous gameplay analytics we collect ourselves, and a request to Google AdMob if you choose to watch a rewarded video.
• There are no banner ads and no in-app purchases. A short full-screen advert may play when you leave a finished puzzle, never during one and never in your first few. Every other advert waits until you press a button marked AD, and if you never do, you will not see an advert.
• We do not collect raw exception messages or stack traces. Limited diagnostics and optional gameplay recording in updated versions are described in the notice above.

What is stored on your device

The App saves the following to your device's own storage:

• the puzzle you are part-way through and the daily puzzle you are part-way through, each holding the digits and pencil marks you have entered, your mistake count, hints used and elapsed time,
• your settings: difficulty, and the highlighting, conflict and auto-clear-notes toggles,
• how many puzzles you have started and finished in each difficulty band, your fastest time in each, and which puzzle number comes next,
• the days whose daily puzzle you completed, your daily reward streak, and a lapsed streak bought back with an advert,
• your pencils balance, which cosmetic colours you own and which you have equipped,
• whether you have finished the guided first puzzle,
• your sound, music and vibration preferences,
• counters for the rating prompt, and the analytics identifier and event queue described in the next section.

Pencils are earned by solving puzzles and spent only on colours. They cannot be bought, and there is nothing in the App to buy.

Your progress never leaves your device. The only exception in that list is the analytics identifier and event queue, which is what the next section is about. All of it is deleted when you uninstall the App or clear its storage in your device settings. We do not collect names, email addresses, contacts, location, photos, files or health data. The App has no way to receive any of them.

What is sent to our own servers

The App sends anonymous gameplay analytics to a server we run at playbrain.games. It is how we find out whether the game is being played and where people stop.

What is sent:

• a random identifier the App generates for itself on first launch, so one installation can be told apart from another, plus a second random identifier for the current session,
• gameplay events: first launch, the app being opened, a puzzle completed or restarted, an optional advert offered and how it ended, whether the rating prompt was shown or skipped, the guided first puzzle being started, finished or abandoned, and the sheet offering our other games being opened or clicked through,
• the app version and the platform.

What is never sent: your name, email or any account (the App has none), your advertising ID or any hardware identifier, your location, anything you typed, or your contacts, photos and files.

That random identifier is not linked to you, is not shared with anyone, is not used for advertising, and is discarded when you uninstall. Events are queued on the device and sent in batches over HTTPS, so playing offline loses nothing. To stop collection, uninstall the App; to ask for deletion, email [email protected].

Rating prompt

The App may occasionally ask you to rate it using Google Play's own in-app review dialog, and only after a win. Google decides whether that dialog actually appears; we only ask. Any rating you leave goes to Google Play, not to us, and we cannot see who left it.

Advertising (Google AdMob)

The App includes Google's Mobile Ads SDK for optional rewarded videos. There are six things a video can buy: an explained next move, filling in one square, a check of your grid for mistakes, filling in every pencil mark at once, keeping your board after three mistakes, and doubling a reward you have just earned. Every button that costs a video is marked AD before you press it. One advert is not optional: a short interstitial may play when you leave a solved puzzle, never during one, never in your first few, and never more often than a fixed cap allows. There are no banner adverts, and every puzzle can be finished without watching a single video: undo, clearing a square, writing pencil marks by hand and starting the same puzzle again are all free and unlimited.

When an ad is requested, Google may collect:

• your device's advertising identifier,
• device information (model, operating system, language, coarse region),
• your IP address,
• interaction with the advert (views, taps).

The App requests non-personalised ads only, which limits Google to using this data for frequency capping, ad measurement and fraud prevention rather than building an advertising profile of you.

If you are in the EEA or the UK, Google's consent form is shown before any ad is ever requested, and nothing is requested until you have answered it. If you decline, the ad SDK is not used at all. The help those buttons offer is then given to you for free instead of being withheld, so declining costs you nothing.

Google's handling of this data is governed by its own policies: Google Privacy Policy and How Google uses information from sites/apps that use its services.

You can reset or delete your advertising identifier at any time in your device settings (Android: Settings → Privacy → Ads).

Our other games

The App has a sheet listing PlayBrain's other games. Choosing one opens its Google Play listing in your browser or in the Play app, with a campaign tag that tells us the visit came from this game. No information about you travels with it, and nothing is sent unless you tap through.

Permissions, audio and the microphone

The App plays sound and music and can vibrate. It does not record audio and has no microphone access: the RECORD_AUDIO permission that the audio library would otherwise request is explicitly blocked, and the audio library is configured with microphone support switched off. Access to external storage, photos and media, screen overlays and background services is blocked in the same place. What remains is the ordinary set a game like this needs: internet access and network state, used for adverts and for the analytics described above, a wake lock declared by the ad library, audio settings, and vibration.

Notifications

The App sends no notifications of any kind. It contains no notification code and no push service.

Children

The App is not directed at children under 13, and we do not knowingly collect any data from them. If you believe a child has provided personal information, contact us and we will address it, though note the App has no mechanism to receive personal information in the first place.

Your rights

We hold no data that identifies you, so there is nothing personal to export or correct. To remove everything the App has stored, uninstall it or clear its storage in your device settings. To ask us to delete the anonymous analytics rows for an installation, email [email protected]. For advertising data held by Google, use the controls linked above.

Changes to this policy

If the App's data practices change, for example if a different ad format or another analytics tool is ever added, this policy will be updated before that version ships, and the date above will change.

Contact

[email protected]