Bitcoin Island Privacy Policy
How the iOS app “Bitcoin Island” processes personal data
Last updated: October 8, 2026 · Deutsche Fassung (the German version is authoritative)
1. Controller
Crimson Dragon UG (haftungsbeschränkt)
Hallstattweg 4
70839 Gerlingen
Germany
Email: info@crimsondragon.de
Legal notice: crimsondragon.de/impressum
2. What the app does
Bitcoin Island shows the current Bitcoin price in euros or US dollars in the app and as a Live Activity in the Dynamic Island and on the Lock Screen. Starting a price session as a Live Activity requires “Bitcoin Island Pro”, a one-time purchase through the App Store.
The app works without an account, without sign-up and without your name or email address. It contains no ads, no analytics and no tracking. Bitcoin Island is not investment or financial advice.
3. Data we process
Fetching the price
To show the price, the app requests it directly from the public CoinGecko API. For technical reasons CoinGecko receives your device's IP address, the time of the request and the requested currency. The app sends no other data.
Updating the Live Activity in the background
So the Live Activity keeps updating while the app is closed, the app sends the following to our update service (bitcoin-api.crimsondragon.de) when you start a session:
- a randomly generated device identifier (created on first use; it contains no hardware ID, advertising ID or Apple ID);
- the Live Activity's push token and, on iOS 17.2 or later, a push-to-start token that lets the service start a follow-up activity after Apple's 8-hour limit;
- the selected currency, the planned session end and the auto-extend setting.
The service fetches the price from CoinGecko at regular intervals and sends it to the Live Activity through the Apple Push Notification service (APNs). This data is kept in memory only and is not stored in a database. A session is removed when it is stopped, expires or Apple reports the push token as invalid, and in any case when the service restarts.
When the app contacts the service, your IP address is processed briefly in memory to prevent abuse (requests per minute are limited); it is not logged. The service's operational logs contain the time, the device identifier and the last eight characters of the push token. They are size-limited and continuously overwritten.
Pro purchase and RevenueCat
For loading the offer, purchasing, restoring and checking Pro access, the app uses the RevenueCat SDK. It is initialized at app launch, even if you never start a purchase. RevenueCat processes:
- an anonymous app user ID generated by the RevenueCat SDK;
- product ID, purchase status and Pro entitlement status;
- store transaction information provided by Apple for purchases, restores, refunds or revocations;
- technical SDK, device, network and diagnostic data, as far as RevenueCat needs it for operation, security and troubleshooting.
Apple handles payment. Neither the app nor our update service receives payment details, store receipts or your Apple ID. RevenueCat may process data outside the European Economic Area; appropriate safeguards are in place for such transfers.
4. Recipients
Depending on the features you use, data may go to:
- the update service, operated by the controller on its own server in Germany;
- Apple, for app distribution, in-app purchase, payment and delivery of Live Activity updates (APNs);
- RevenueCat, Inc., for purchase status, restores and entitlement checks;
- CoinGecko as the price source, receiving only the connection data that a request involves.
We do not share data for advertising.
More information:
5. Purposes and legal bases
- Fetching the price, displaying it and updating the Live Activity: Art. 6(1)(b) GDPR, as required to provide the feature you started.
- Processing and restoring the one-time Pro purchase: Art. 6(1)(b) GDPR.
- Abuse prevention and operational logs: Art. 6(1)(f) GDPR (secure and stable operation).
- Statutory record-keeping, tax and retention obligations: Art. 6(1)(c) GDPR.
6. Retention and deletion
- Session data in the update service: until the session ends, at the latest until the service restarts (no persistent storage);
- IP addresses for abuse prevention: in memory for the current one-minute window only;
- operational logs: size-limited and continuously overwritten;
- purchase and entitlement status at RevenueCat and Apple: as needed for providing and restoring Pro and for required records;
- data stored locally on your device: until you delete the app.
7. On-device storage and permissions
The app stores the device identifier and settings (such as the selected currency) locally on your device. You can turn off Live Activities for Bitcoin Island in iOS Settings at any time; the price view in the app keeps working. The app requests no other permissions.
8. Your rights
Subject to the legal requirements, you have the right of access, rectification, erasure, restriction of processing, data portability and objection. You also have the right to lodge a complaint with a data protection supervisory authority.
Send requests to info@crimsondragon.de. Because the update service stores no persistent user data, stopping the session or deleting the app is usually enough to remove the device identifier.
9. Changes
We update this policy when features, recipients or legal bases change.
Use of the app is governed by the Apple Standard EULA.
Website privacy policy: crimsondragon.de/privacy