Privacy Policy

Last updated: 18 August 2026 · Deutsche Version

This policy explains what data the Langust app ("Langust", "we", "us") processes, why, and the choices you have. Langust is a language-learning app for iOS and Android.

1. Who is responsible

The controller for your data is SevenCourts GmbH (the "Company"). For any privacy question or to exercise your rights, contact us at privacy@langust.app.

2. Data we process

Your learning content stays on your device. Your decks, cards and study progress are stored locally on your device. We do not upload them to our servers or keep them in an account.
AI example generation. When you ask the app to generate an example for a word, the word or phrase and your generation settings are sent to our service and to our AI provider — currently Mistral AI (France) — to produce the example. Please do not enter sensitive personal information into these fields.
Translation. Text you choose to translate is sent through our service to the same AI provider as above (Mistral AI, France) to return the translation.
Device registration. To use the built-in AI service we issue an anonymous token to your device. This does not require your name or email.
Reminders & notifications. If you turn on reminders, we register a push notification token for your device and record lightweight activity signals on our server — when you open the app or complete a study session, your time zone and app language, how long local reminders cover your device, and when we last sent you a notification. We use these only to schedule study reminders and re-engagement notifications (for example, after you have been away) at a sensible local time, and to deliver them through Apple Push Notification service and Firebase Cloud Messaging. This data is tied to the anonymous device token, not to your identity. We do not use this information for advertising or cross-app tracking. You can turn reminders off at any time in Settings, which stops them and deletes the push token from our server.
Analytics & diagnostics. We use Google Firebase Analytics and Crashlytics to understand how the app is used and to receive crash reports. This includes app-usage events, approximate device and OS information, and crash logs, tied to a pseudonymous identifier — not your name.

3. Why we process it (legal bases)

Under the GDPR we rely on: performance of a contract (providing the app) and our legitimate interests (operating the app, keeping it stable and secure, diagnosing crashes, understanding feature usage, preventing abuse, and improving the product). Analytics and diagnostics are currently active by default; the app does not provide an in-app switch for them.

4. Who we share it with

We share data only with service providers that help us run the app, acting as our processors or as independent controllers for their part:

Google — Firebase Analytics & Crashlytics, and Firebase Cloud Messaging for delivering notifications.
Apple — Apple Push Notification service, for delivering notifications on iOS.
Mistral AI (France) — generating example sentences and translations.
Our hosting provider, for the AI-generation and notification-scheduling service.

Some of these providers may process data outside the EU/EEA (e.g. in the United States); where they do, appropriate safeguards such as the EU Standard Contractual Clauses apply. We do not sell your personal data.

5. How long we keep it

Your decks, cards and progress live on your device and are removed when you delete them or uninstall the app. Your push token is kept only while reminders are enabled and is deleted from our server when you turn reminders off. A record of each notification we send (which template and when, but not its content) is kept for up to 90 days for delivery diagnostics, then deleted. Retry-protection event identifiers are deleted after 30 days. Uninstalling the app does not itself notify our server. Analytics and crash data are retained for a limited period per the provider's settings. Text you send for AI generation or translation is processed by those providers under their own retention policies.

6. Your rights

We don't store personal data that identifies you by name — your content stays on your device, and the data we do collect (analytics, crash reports, the push token and activity signals) is pseudonymous and tied to an anonymous device token. You may object to processing based on our legitimate interests on grounds relating to your particular situation. If you have any privacy question, objection or other request, email privacy@langust.app.

7. Children

Langust is not directed to children under 16, and we do not knowingly collect their data. The app has no accounts and keeps learning content on the device. The limited server-side data described above, including analytics, diagnostics and notification data, is pseudonymous and is not tied to a name or email address. If you have concerns, email privacy@langust.app.

8. Security

We use reasonable technical and organisational measures to protect your data, including encryption in transit. No method of transmission or storage is completely secure, so we cannot guarantee absolute security.

9. Changes to this policy

We may update this policy from time to time. The "last updated" date above reflects the latest version; material changes will be highlighted in the app or on this page.

Contact: privacy@langust.app · SevenCourts GmbH · Impressum