LetterGuardLast updated: October 2026. The German version (Datenschutzerklärung) is legally binding.
Privacy policy
1. Controller
WK IT Services, Jahnstraße 8, 74861 Neudenau, Germany (sole proprietorship, owner: Waleed Ahmed Khan) – [email protected]
2. In short
No account, no tracking, no ads. Letter images, your archive and your personal data stay on your phone, encrypted.
3. Processed on your device only
Letter scans (images), text recognition (Google ML Kit, on device), your archive, deadlines and reminders, and the personal data you enter for masking. App data is excluded from Android cloud backup (Google Drive).
4. Sent to our server
Only the recognised letter text, after personal details (names, addresses, IBAN, tax ID, insurance, customer and file numbers, phone numbers, emails, and the data you entered) have been replaced with placeholders on your device. Automatic masking cannot guarantee that every personal detail is detected. Also sent: the chosen language, today's date and a random device ID used to count your free monthly analyses.
Legal basis: Art. 6(1)(b) GDPR (providing the service) and Art. 6(1)(f) GDPR (abuse prevention). The letter text is not stored. Only the random device ID with a counter is kept, for at most 40 days.
5. Processor
Cloudflare, Inc., San Francisco, USA – server hosting (Cloudflare Workers) and AI processing (Cloudflare Workers AI), under a data processing agreement. Cloudflare is certified under the EU-US Data Privacy Framework; standard contractual clauses apply additionally. According to Cloudflare, Workers AI inputs are not used to train AI models.
6. Google Play
The app is distributed via Google Play; Google's privacy policy applies to downloads, purchases and updates. Scanner and text recognition use Google ML Kit / Google Play services on your device, which may collect technical diagnostics.
7. Your rights
You have the rights of access, rectification, erasure, restriction, portability and objection (Art. 15–21 GDPR) and may complain to a data protection authority. Uninstalling the app deletes all data stored on your device.