Privacy Policy

Last updated: March 2026

1. Who we are

BriefKlar is a free, open-source desktop application for Windows developed by Maria Fe Fischer. The app is available at github.com/MfFischer/briefklar.

2. What data BriefKlar processes

When you scan a letter, BriefKlar processes the following data locally on your device only:

• The photo image taken with your phone
• The OCR text extracted from the photo
• Classification results (letter type, sender, deadline, amount)
• Any corrections you make ("Was this wrong?" feedback)
• Your language preference

All of this data is stored in a SQLite database file on your computer at %APPDATA%\BriefKlar\briefklar.db. You can delete this file at any time to remove all data.

3. What data BriefKlar does NOT collect

• No data is uploaded to any server
• No analytics, crash reports, or telemetry
• No account registration or login
• No cookies (this is a desktop app, not a website)
• No advertising identifiers

4. Internet connections

BriefKlar makes no outbound internet connections during normal operation. The only time an internet connection is used:

• Optional AI replies: If you choose to use the AI reply feature with your own Gemini API key, your letter text is sent to Google's Gemini API. This is entirely optional and requires you to provide your own API key.
• Mobile scan: The local QR code handoff server operates on your local WiFi network only — no data leaves your network.

5. Third-party libraries

BriefKlar uses the following open-source libraries, all of which operate locally:

• Tesseract.js — OCR engine (runs locally, no data sent anywhere)
• better-sqlite3 — local database storage
• Electron — desktop app framework
• Sharp — local image processing

6. Children's privacy

BriefKlar does not knowingly collect any information from children under 13. As no data is collected at all, this is not applicable.

7. Your rights

Since all data is stored locally on your device, you have full control over it at all times. You can:

• View all data in the app's dashboard
• Delete individual letters from the dashboard
• Delete all data by removing %APPDATA%\BriefKlar\
• Uninstall the app completely using Windows Settings

8. Changes to this policy

If this policy changes, the updated version will be posted at this URL. Significant changes will be noted in the app's changelog on GitHub.

9. Contact

Questions about privacy? Open an issue on GitHub.