Privacy Policy for Cairn
Last updated: 24 July 2026
Cairn is a puzzle game published by Bllearcorp. This policy explains what information the app and the services inside it handle, and what you can do about it.
The game itself collects nothing. The advertising in it does, and most of this policy is about that.
1. What Cairn itself collects
Nothing. Cairn has no account system, no sign-in, no analytics of its own and no crash reporting. It does not ask for your name, your email address, your precise location, your contacts or your photos, and it contains no code of its own that sends anything anywhere.
2. What is stored on your device
Your progress is saved on your own device and nowhere else. That save holds only:
- which levels you have solved, and in how many moves
- which levels you have set aside
- your daily-puzzle streak and the last day you played
- your settings: theme, sound, haptics and motion
- whether you have bought Remove Ads
It lives in the app's private storage, no other app can read it, and it never leaves your device. Uninstalling Cairn deletes it. You can also clear your progress from inside the app with Settings → Start over, which keeps your settings and your Remove Ads purchase — see section 4.
The advertising libraries keep a little of their own state on your device as well: your recorded consent choice, and counters used to avoid showing you the same ad too often. It is held in the app's private storage and is removed when you uninstall Cairn.
3. Advertising
Cairn is free and is paid for by advertising. Ads are supplied by Google AdMob, a Google service. AdMob may also source an ad from another advertising network through Google's mediation and bidding, in which case that network receives the same information described here.
To show ads, to measure them and to detect fraud, the Google Mobile Ads SDK collects information from your device and shares it with Google. Google publishes the list, and this is it in full:
- IP address — used, among other things, to estimate the general region of your device.
- App interactions — app launches, taps and video views, including that an ad was shown in Cairn and whether you tapped it.
- Diagnostics — how the app and the ad SDK performed: launch time, hang rates, energy usage.
- Device and account identifiers — your Android advertising ID (a resettable identifier Android provides for advertising), the app set ID, and account-related identifiers.
Google collects and shares all four for advertising, analytics, and fraud prevention, security and compliance, and encrypts them in transit using TLS. Google may combine this information with information it already holds from its other services in order to choose the ads you see. The current list is published at developers.google.com/admob/android/privacy/play-data-disclosure.
Who is responsible for it. Bllearcorp does not operate a server, and nothing in this app sends us anything. But we choose to show advertising and we see aggregate reports of how it performed, so for that advertising we and Google are each responsible in our own right for the information described above. Google handles it under its own policies:
Where the ads appear. Ads are shown on the menu screens, and occasionally after you finish a level and choose to move on. No ad is ever shown while a puzzle is on screen, and none will interrupt a puzzle you are in the middle of.
Personalised ads, and your choice
Where the law requires it — in the European Economic Area, the United Kingdom and Switzerland — Cairn asks for your consent before any personalised advertising, through a Google-certified consent platform, and asks before the first ad is requested. You may refuse, in which case you will see non-personalised ads: ads chosen from general context rather than from a profile. Refusing does not restrict any part of the game. You can change or withdraw the choice at any time from Settings → Privacy options.
Turning it off yourself
Independently of anything in the app, you can:
- Reset or delete your advertising ID in Android Settings → Privacy → Ads. Deleting it withdraws the identifier from every app on the device.
- Buy Remove Ads, which stops the app requesting any ad at all.
4. Purchases
Cairn offers one optional one-time purchase, Remove Ads. Buying it permanently stops all advertising in the app for you.
Purchases are handled entirely by Google Play Billing. Your payment details are entered in Google's own interface and are never seen by, sent to, or stored by Bllearcorp or by Cairn. The app receives only the fact that the purchase is owned, and records that on your device.
Because it is a non-consumable purchase tied to your Google account, reinstalling Cairn and signing in with the same account restores it. There is also a Restore purchase row in Settings. Start over deliberately does not remove it: resetting your progress must not take away something you paid for.
5. Permissions
Cairn requests:
- Vibrate (
android.permission.VIBRATE) — the small haptic tap when a stone settles. Turn it off in Settings → Haptics. - Internet (
android.permission.INTERNET) and network state (android.permission.ACCESS_NETWORK_STATE) — used by the advertising SDK to fetch ads and by Google Play Billing. The puzzles themselves need no connection and are fully playable offline. - Advertising ID (
com.google.android.gms.permission.AD_ID) — declared by the Google Mobile Ads SDK and merged into Cairn's manifest by the Android build. It lets the ad SDK read the resettable advertising identifier Android provides.
Cairn does not request your precise location, contacts, files, photos, camera or microphone.
6. Children
Cairn is not directed at children. It is intended for players aged 13 and over, and it is declared that way on Google Play.
Cairn does not knowingly collect personal information from children under 13. In the European Economic Area, the age at which a person can consent to a service like this on their own is set by each country and is between 13 and 16; if you are below the age set in your country, do not consent to personalised advertising — ask a parent or guardian. In California we do not sell or share the personal information of anyone we know to be under 16.
If you believe a child has provided information through the advertising in this app, write to the address in section 9 and we will act on it.
7. If you are in the European Economic Area, the United Kingdom or Switzerland
Who is responsible. Bllearcorp — contactable at the address in section 9 — is the controller for personal data collected through Cairn. Google is an independent controller for the data it collects through the AdMob SDK; for users in these regions that is Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland.
Why, and on what basis:
| What | Why | Legal basis |
|---|---|---|
| Advertising ID, app set ID, IP address, ad interactions, diagnostics — collected by the Google Mobile Ads SDK | Storing and reading identifiers on your device; showing, capping, measuring and billing ads; detecting fraud | Consent, taken before the first ad request |
| Personalisation of those ads | Choosing ads from a profile rather than from context | Consent |
| Your Google Play purchase of Remove Ads | Providing what you paid for, and honouring restores | Performance of a contract |
| Your progress and settings | Running the game | Stays on your device; nothing is transferred to us |
Withdrawing consent. Change or withdraw it at any time from Settings → Privacy options. Withdrawal does not affect the lawfulness of anything done beforehand, and restricts no part of the game.
Security. Everything the advertising SDK sends is encrypted in transit using TLS. Your save is held in the app's private storage, readable by no other app. Bllearcorp operates no server.
Retention. Bllearcorp holds no personal data about you, so it retains none. Your save stays on your device until you use Start over or uninstall Cairn. Data collected by Google is retained under Google's own policy: policies.google.com/technologies/retention.
International transfers. Google processes advertising data on servers outside the EEA and the UK, including in the United States, relying on the EU–US and UK–US Data Privacy Framework and on the European Commission's Standard Contractual Clauses. See policies.google.com/privacy.
Your rights. You may ask what is held about you, and ask for it to be corrected or deleted. Because Bllearcorp holds nothing, such requests are almost always for Google — the links above are the route. For anything else, write to us.
Complaints. You may lodge a complaint with a supervisory authority: in the EEA, the authority where you live or work (edpb.europa.eu); in the UK, the ICO (ico.org.uk/make-a-complaint); in Switzerland, the FDPIC (edoeb.admin.ch).
8. If you are in California
Notice at collection. When Cairn shows an ad, these categories of personal information are collected from your device: identifiers (advertising ID, app set ID); internet or other electronic network activity (that an ad was shown and whether you tapped it; app and SDK diagnostics); coarse geolocation (the approximate region derived from your IP address); and inferences (advertising interests Google infers, if you allow personalised ads). The purposes are showing and measuring advertising, analytics, and preventing fraud. The category of third party receiving it is advertising networks — specifically Google. Cairn collects no sensitive personal information.
Sale and sharing. Bllearcorp does not sell your personal information for money. But disclosing your advertising ID and IP address to Google so that Google can select personalised ads is a share for cross-context behavioural advertising, and some states treat the same disclosure as a sale. We treat it as both.
Your right to opt out. Use Settings → Privacy options and decline personalised advertising. Buying Remove Ads stops all advertising outright.
Your other rights. You may ask what we hold, ask us to delete it, or ask us to correct it, and we will not treat you differently for asking. Write to the address below.
9. Changes, and how to reach us
If a future version of Cairn changes what is collected — a different ad network, or anything the game itself gathers — this policy will be updated before that version is published, and the date at the top will change.
Questions about this policy, or about privacy in Cairn:
minecraft77x@gmail.com
Bllearcorp