Privacy Policy

LangYOU is designed with a privacy-first approach. Most of your data stays on your device. **Data stored on your device only:** - Your vocabulary (saved words and translations) - Imported books and reading progress - Learning statistics and exercise results - App preferences and settings - Spaced repetition schedules **Data we process on our servers:** - AI exercise evaluation requests (word, translation, sentence text — sent to our API at lang.hashlab.digital) - An anonymous device identifier for AI requests - Vocabulary sync data (if you use cloud sync features) - App interface translations for your selected language **Data processed by third-party services:** - Word translations via LibreTranslate and MyMemory APIs - Dictionary definitions via Free Dictionary API - Example sentences via Tatoeba API - Crash reports via Firebase Crashlytics (if enabled) - Subscription status via Apple StoreKit

LangYOU uses a hybrid AI approach: **On-device AI:** An AI language model (downloaded once, ~1.3GB) runs entirely on your iPhone to generate contextual example sentences. No data leaves your device for this feature. **Cloud AI:** For exercise evaluation, hints, and the AI tutor chat, text data (words, translations, sentences) is sent to our server at lang.hashlab.digital. An anonymous device identifier is included with these requests. No personal information such as name or email is sent.

Premium subscriptions are managed entirely through Apple's App Store. We do not collect or store your payment information. Apple handles all billing, receipts, and subscription management according to their privacy policy.

LangYOU uses the following third-party services: - **Apple StoreKit** — for subscription management - **Firebase Crashlytics** — for anonymous crash reporting (can be disabled) - **Tatoeba** — for example sentences (open-source sentence database) - **LibreTranslate** — for word translations (open-source translation API) - **MyMemory** — as a fallback translation service - **Free Dictionary API** — for word definitions and phonetics These services receive only the minimum data needed to function (e.g., the word being translated). No personal identifiers are sent to third-party services.

We do not sell or share your personal data with third parties for advertising or marketing purposes. Data is only sent to the services listed above for core app functionality (translation, example sentences, AI exercises). Your vocabulary and reading data are never shared with advertisers or data brokers.

All learning data is stored locally on your device. Vocabulary sync data may be stored on our servers at lang.hashlab.digital if you use sync features. You can delete all app data at any time by removing the app or using the in-app reset function.

LangYOU does not knowingly collect personal information from children under 13. The app is suitable for all ages but does not target children specifically.

You have the right to: - Access all your data (it is on your device) - Delete all your data (via app deletion or in-app reset) - Opt out of crash reporting - Request information about data processing - Contact us at [email protected] for any privacy concerns

We may update this privacy policy from time to time. Changes will be posted on this page with an updated revision date.

If you have questions about this privacy policy, please contact us at [email protected].