Privacy Policy
Last updated: October 6, 2026
This privacy policy explains how we collect, use, and protect your personal data when you use the Lingoo iOS app and the website lingoo.io.
1. Data Controller
Julian Blöchl – Sole Proprietor Keferloherstraße 45 80809 Munich Germany Email: julian@bloechl.io
2. Hosting and Infrastructure
The website lingoo.io is hosted by Vercel Inc. The Lingoo API that the iOS app communicates with, and the scheduled job that sends daily reminders, run on Railway (Railway Corp., USA). Your account data, learning content and progress are stored in a MongoDB Atlas database (MongoDB, Inc.). Generated audio files are stored on Cloudflare R2 (Cloudflare, Inc.). All of these providers act as processors in accordance with Art. 28 GDPR. We have entered into data processing agreements with them that provide for appropriate technical and organisational measures. Where personal data is transferred to the United States, the transfer is based on the standard contractual clauses approved by the EU Commission.
3. Account and Profile Data
To create and operate your account we process your name, your email address and — if you register with a password — that password as a salted hash. We never store your password in plain text. If you use Sign in with Apple, we additionally store the pseudonymous Apple user identifier and the email address Apple passes on to us. If you choose Hide My Email, this is an anonymised Apple relay address and we never learn your real address. We also store the learning preferences you set: your native language, the languages you are learning, your level, your learning goals and interests, and your app language. The legal basis is performance of the contract (Art. 6 para. 1 lit. b GDPR). This data is deleted when you delete your account.
4. Learning Content and Progress
Using Lingoo produces content that we store against your account so that your progress is available on every device you sign in on. This includes in particular: • your messages in conversation and chat sessions; • your answers to exercises, including the evaluation of those answers; • topics and prompts you enter yourself; • the stories, exercises and explanations generated for you; • your placement test and its result; • your vocabulary and grammar progress, including review history and due dates; • your session history and learning statistics. We process this data to provide the service and to adapt the difficulty and the content of your next session to your progress (Art. 6 para. 1 lit. b GDPR). It is deleted when you delete your account.
5. Voice Input and Transcription
Speaking exercises are optional. You can complete every exercise by typing instead, and the app only asks for microphone access once you actually start a recording. When you record an answer, the recording is transmitted to our API and forwarded from memory to one of our AI providers (see section 6) for transcription. Lingoo does not write the recording to disk and does not store it. Only the resulting text is saved as part of your session (see section 4). The legal basis is performance of the contract (Art. 6 para. 1 lit. b GDPR).
6. AI Providers and AI-Generated Content
Stories, exercises, conversation replies, feedback, vocabulary explanations, transcriptions and spoken versions of texts are created with AI models from external providers. Depending on the feature, we use one or more of the following providers: • OpenAI, Inc. (USA) • Google LLC (USA) or Google Ireland Limited (Ireland) • Anthropic, PBC (USA) Which provider is used for which feature may change, for example when another model delivers better results. To do this we transmit the learning context required for the request — for example your level, the selected topic, the vocabulary or grammar being practised, your previous answers in the current session and, where applicable, your voice recording. We do not transmit your name, your email address or any payment data. Before you use the AI features for the first time, we ask for your consent to this transfer in the app. Lingoo cannot be used without this consent, because all learning content is created with AI. You can withdraw your consent at any time by deleting your account (see section 14) or by writing to julian@bloechl.io. All AI providers named above act as our processors under Art. 28 GDPR. We use their commercial API offerings, for which, according to the providers, submitted data is not used to train their models. The providers may retain request data for a limited period for abuse monitoring. Transfers to the USA are based on the EU standard contractual clauses. AI-generated content can be factually wrong or unsuitable despite our safeguards. Please do not rely on it for medical, legal or financial decisions. The legal basis is performance of the contract (Art. 6 para. 1 lit. b GDPR).
7. Generated Audio Files
Spoken versions of texts are generated with the text-to-speech of one of our AI providers (see section 6) and stored on Cloudflare R2 so that the same sentence does not have to be generated again for every learner. The file name of such an object is derived from a cryptographic hash of the spoken text, the voice and the language — not from your account. The same file is therefore reused across users. The objects are served from a public URL that anyone who knows it can retrieve; the URL contains no personal data and is not linked to your identity. Because these objects are shared and cannot be attributed to an individual account, they are not deleted when you delete your account.
8. Premium Subscription
When you subscribe to Premium, we process your access data and usage information about the subscription (for example activation time, product, expiry, renewal status). This data is necessary to grant premium access, prevent abuse and fulfil our contractual obligations (Art. 6 para. 1 lit. b GDPR). We do not process payment data; the purchase is handled by Apple (see section 9).
9. Payment Processing via Apple and Subscription Management
Premium subscriptions are purchased as in-app purchases through the Apple App Store. Payment is processed entirely by Apple. We receive no payment data from Apple – in particular no credit card or bank details. Apple is itself responsible for its processing of your data; details can be found in Apple's privacy policy at https://www.apple.com/legal/privacy/. To manage and verify subscription status we use RevenueCat, Inc. (USA) as a processor pursuant to Art. 28 GDPR. This involves a pseudonymous user identifier, the purchased product ID, purchase date, expiry date and device data – but not your payment data. The legal basis is performance of the contract (Art. 6 para. 1 lit. b GDPR). For the transfer to the USA we have entered into the standard contractual clauses approved by the EU Commission. Further information is available at https://www.revenuecat.com/privacy.
10. Push Notifications
Daily learning reminders are optional. If you allow notifications, we store the device token that Apple issues for your device, your time zone, your reminder settings, and a record of which reminder was delivered on which day so that the same reminder is not sent twice. The content of a reminder is derived from your learning progress. Delivery runs through the Apple Push Notification service (Apple Inc.). The legal basis is your consent, which you give in the iOS system dialog (Art. 6 para. 1 lit. a GDPR). You can withdraw it at any time in the iOS settings or in your Lingoo profile. Device tokens and delivery records are deleted when you delete your account.
11. Email Communication
For sending transactional emails (e.g., registration confirmation, password reset, support), we use Resend, 2261 Market Street #5137, San Francisco, CA 94114, USA. Resend processes email addresses, names, content data, and technical delivery information. Processing is carried out to fulfil the contract or based on our legitimate interest in reliable communication (Art. 6 para. 1 lit. b and lit. f GDPR). Resend bases data transfers to the USA on recognised guarantees; further information can be found in Resend's privacy policy at https://resend.com/legal/privacy.
12. Server Logs and Usage Records
When the app or the website calls our API, server log data is processed automatically: IP address, date and time of the request, the endpoint called, the HTTP status, and technical client information such as browser or app version and operating system. This serves the technical provision of the service and the safeguarding of system security (Art. 6 para. 1 lit. f GDPR) and is deleted after at most 30 days. We additionally record one entry per AI request containing the time, the model used, the number of tokens, the duration, the status and your user ID, so that we can monitor cost and reliability. These entries contain no message content and are deleted automatically after 90 days.
13. Storage Duration
We store personal data only as long as necessary to fulfil our contractual and legal obligations: • Account, profile, learning content and progress: until you delete your account. • Subscription data: deleted or anonymised at the latest 30 days after the subscription ends. • Push tokens and notification delivery records: until you delete your account or switch notifications off. • Server logs: at most 30 days. • AI usage records: 90 days, deleted automatically. • Generated audio files on Cloudflare R2: stored indefinitely. They are content-addressed, shared between all users and not linked to your account (see section 7). Statutory retention obligations take precedence where they apply.
14. Deleting Your Account
You can delete your account at any time in the app under Profile > Delete account. No email to us is required. Deletion permanently removes your user record, your login sessions, your learning sessions, practice sessions, conversations, stories, placement tests, vocabulary progress, notification delivery records and your learning history from our database. If you signed in with Apple, your Sign in with Apple authorisation for Lingoo is revoked with Apple at the same time. Two categories are not covered by this and are described separately: generated audio files on Cloudflare R2, which are shared and not attributable to you (section 7), and AI usage records, which expire automatically after 90 days (section 12). Important: deleting your account does not cancel an active App Store subscription. App Store subscriptions belong to your Apple account and can only be cancelled there. Please cancel in your Apple subscription settings before deleting your account, otherwise Apple will continue to charge you.
15. Data Sharing and Recipients
We only share personal data with third parties where this is necessary to fulfil the contract, you have consented, or we are legally obliged to do so. We do not sell personal data and we do not use it for advertising or cross-app tracking. The recipients are the processors named in this policy: • Railway Corp. (USA) – operation of the API and background jobs • MongoDB, Inc. – database for account, learning and progress data • Cloudflare, Inc. – storage and delivery of generated audio files • OpenAI, Inc. (USA), Google LLC (USA) or Google Ireland Limited, Anthropic, PBC (USA) – transcription, text generation and speech synthesis (see section 6) • RevenueCat, Inc. (USA) – subscription status • Apple Inc. – purchase processing, Sign in with Apple, push delivery • Resend (USA) – transactional email • Vercel Inc. – hosting of the website Transfers to third countries only take place where adequate safeguards under Art. 46 GDPR are in place, in particular the EU standard contractual clauses.
16. Your Rights
You have the right to information, correction, deletion, restriction of processing, data portability, and objection to the processing of your personal data. If you have given us consent, you can revoke it at any time. Contact julian@bloechl.io for this. You also have the right to complain to a data protection supervisory authority.
17. Security
We use technical and organisational security measures to protect your data from manipulation, loss, destruction or unauthorised access. Traffic between the app and our API is encrypted in transit, passwords are stored only as salted hashes, and access tokens are held in the iOS keychain. Our measures are based on current state-of-the-art technology and are reviewed regularly.
18. iOS Beta Requests
When you join the Lingoo iOS beta list, we process your name, email address, selected website language, and the time and number of your requests. We use this data solely to organise the beta and contact you about invitations or important beta information. The legal basis is your consent under Art. 6(1)(a) GDPR. You may withdraw your consent at any time by emailing julian@bloechl.io. We delete your beta request after the beta phase ends, or earlier if you withdraw your consent, unless legal obligations require otherwise.