Privacy policy

Last updated: 19 October 2026

GutenTalk is an Android app for learning to speak German. It's built to work on your phone: lessons, pronunciation scoring, speech recognition, flashcards and the offline conversation partner all run on the device. You don't need an account.

1. Who is responsible

GutenTalk is made by an individual developer, who is the data controller for the data described here.

Controller

William Bennatt, United States

Contact

[email protected]

The website you're reading sets no cookies and uses no analytics. Our web host processes the technical data any website request involves (such as your IP address) to deliver the pages and protect against abuse.

2. Microphone and recordings

• The app records audio only while you tap the record button.
• Recordings are processed on your phone for pronunciation scoring and speech recognition. They are never uploaded.
• The latest attempt for each line is kept on your phone so you can listen back. With Save my recordings (off by default) the app keeps all your attempts, still only on your phone.

3. Account (optional)

You can create an account to sync your progress between devices. You sign in with your email address (we send you a one-time code or link) or with Google.

Your account is stored by Supabase, on servers in the European Union. It holds your email address and, if you use Google sign-in, the name and profile information Google provides.

4. Sync (optional)

When you're signed in with sync turned on, the following is stored with your account so it appears on your other devices:

• your learning profile (level, rating, goals);
• practice history: sessions, exercise results, per-line scores (as numbers) and practice minutes per day;
• flashcards and their review history;
• statistics on which German sounds you find difficult;
• some app settings.

Not synced: recordings and the transcripts of your conversations in Talk. Each account can only read and change its own data (enforced in the database by row-level security).

5. Online AI on your own Claude key (optional, off by default)

The conversation partner, Lena, runs on your phone. If you prefer, you can enter your own API key for Anthropic's Claude and turn on online Talk or online answer checking. Then:

• the text of your sentences and the conversation (never audio) is sent directly from your phone to Anthropic, under your own Anthropic account. It doesn't pass through GutenTalk's servers and we can't see it;
• Anthropic's privacy policy and the terms of your Anthropic account apply to that data, and Anthropic bills you for the usage;
• your API key is stored only on your phone.

6. Reporting AI replies

If you report a reply or correction from the conversation partner, we receive: the reported text, your sentence before it, the reason you chose, your optional note, the scenario, your level and the app version. We use this to review and fix problems. Reports are anonymous: they aren't linked to your account.

7. Crash reports (optional, off by default)

With Settings → Send crash reports turned on, the app sends reports when it crashes or freezes: the error and its stack trace, the app version, your phone model and Android version. Nothing about you or your practice. Without your consent, crash information stays on your phone and is deleted after 30 days.

8. Downloads

On first use the app downloads speech models from Hugging Face (huggingface.co) and, if you choose, the conversation model. Newer lesson packs come from GutenTalk's storage at Supabase. Like any download, these requests reveal your phone's IP address to the server that answers them. No account or practice data is sent with them.

9. Google services on your phone

Lena speaks through your phone's text-to-speech engine, usually Google's. The daily reminder uses Android's notifications. Google Play may collect diagnostics if you allowed it in Android's settings; Google's privacy policy governs that, not this one.

10. How long data is kept and how to delete it

• Account and synced data are kept until you delete your account. Deleting it removes your account and all synced data immediately. You can delete it in the app (Settings → Account → Delete account) or on this website.
• AI reports and crash reports aren't linked to an account. They're kept for up to 6 months and then deleted.
• Data on your phone is removed when you uninstall the app, or with the delete options in Settings.

11. Service providers

• Supabase: hosting, database and authentication, with data stored in the EU.
• Our email provider: sends sign-in emails to the address you enter.
• Google: only if you choose to sign in with Google.
• Cloudflare: hosts this website.

These providers process data only on our instructions. Anthropic isn't our service provider: if you use online AI, you send your text to Anthropic yourself, on your own account. Some providers are based in the United States; where personal data is transferred outside the EU, it's protected by the EU's standard contractual clauses or an adequacy decision.

We don't sell your data and we don't share it with anyone for advertising.

12. Your rights and legal bases

Because our servers are in the EU, the EU General Data Protection Regulation (GDPR) applies. You have the right to:

• access the data we hold about you;
• have it corrected;
• have it deleted (see section 10);
• receive it in a portable format: the app has Export my data in Settings;
• object to processing based on legitimate interests, and withdraw consent at any time (for example by turning a setting off);
• complain to a data protection supervisory authority, in particular in the EU country where you live or work.

To use these rights, email [email protected]. We answer within one month.

We rely on these legal bases:

• Contract (Art. 6(1)(b) GDPR): your account and sync.
• Consent (Art. 6(1)(a)): crash reports and online AI.
• Legitimate interest (Art. 6(1)(f)): handling reports of AI replies, to keep the conversation partner safe and accurate.

13. Children

GutenTalk is intended for adults (18 and over) and is not directed at children. If you believe a child has created an account, contact us and we'll delete it.

14. Changes to this policy

If we change this policy, we'll update the date at the top. If a change affects how your data is used in a significant way, we'll also tell you in the app.