KarlLang Privacy Policy

Last updated: 13 June 2026

KarlLang (“the App”) is a typing-based vocabulary learning application for adult learners. This privacy policy explains what data the App handles and how it is used.

1. Account and sign-in

KarlLang can be used without creating an account.

If you choose to sign in with Apple or Google, KarlLang may receive and store the account identifier and email address provided by the sign-in provider. This information is used only to provide account access and cloud sync features.

2. Data collected and stored

KarlLang may handle the following data:

• Study settings, such as study language, UI language, study mode, level, category, and word count
• Word learning progress, such as review level, due dates, correct or wrong results, mistakes, bookmarks, and hard words
• Study statistics, such as reviewed word counts, attendance, streaks, and learning summaries
• App preferences, such as sound, haptic, and reminder settings
• Account information provided through Apple or Google sign-in, such as email address and account identifier

If you use KarlLang in guest mode, learning data is primarily stored on your device.

If you sign in and use cloud sync, your learning data may be stored on KarlLang’s backend service so that it can be synchronized across your devices.

3. Cloud sync

KarlLang provides optional cloud sync for signed-in users.

Cloud sync may store and synchronize:

• Study settings
• Word progress