Privacy policy

Last updated: October 5, 2026

1. Who is responsible

The FerriCheck app and this website are published by Coudray Nathan (Aydong), Swiss - Wallis. For any question about your data: contact@ferricheck.ch.

2. Data stored in the app

You can enter in FerriCheck:

• your ferritin measurements (date, value, note);
• your blood removals, donations and phlebotomies (date, type, volume, note);
• your blood group and donor number;
• your settings: target range, interval between two removals, appearance, language.

This data is stored only on your device. It is not sent to the publisher or to any third party: the app does not have the permission to access the Internet. There is no account, no server and no synchronization.

3. Security

• The database is encrypted. Its key is created on your phone and kept in its secure storage.
• The fingerprint, face or PIN lock is handled by your phone: the app never receives your biometric data, only the result of the check.
• Android’s automatic backups (cloud and transfer to a new device) are disabled for the app.

4. Backups and exports

Only you can take your data out of the app, by creating a backup encrypted with a password or a CSV export. A CSV file is not encrypted: anyone who gets it can read it. You choose where these files are kept; if you put them on an online service, that service’s policy applies.

5. Permissions

The app asks for access to the biometric sensor, for the app lock, and a few technical permissions needed by the home screen widget. It does not access your contacts, your location, your camera or your microphone.

6. Third-party services

The app contains no ads, no analytics and no crash reporting sent to the publisher. It is distributed through Google Play: Google processes the data related to downloads and updates under its own privacy policy.

7. Retention and deletion

Your data stays on your device until you delete it. You can erase everything from the settings (“Delete all data”) or by uninstalling the app.

8. Your rights

The Swiss Federal Act on Data Protection (FADP) and, where it applies, the European regulation (GDPR) give you in particular a right of access, rectification and erasure. As the publisher holds none of your data, you exercise these rights directly in the app: you can view, edit, export and delete your data at any time.

9. This website

This website uses no cookies, no trackers and no forms, and loads nothing from another site. If you switch between the light and dark theme, that choice is remembered in your browser only; it is not sent to us. Like any web server, the hosting provider may keep technical logs (IP address, date, requested page) to run and secure the service.

10. Changes

If this policy changes, the new version will be published on this page, with its update date.