Stand: May 2025
This privacy policy provides you with detailed and transparent information in accordance with the legal requirements of the General Data Protection Regulation (GDPR) about the type, scope, and purpose of the processing of personal data within our mobile application "BrainCell.". We also explain your rights in relation to the processing of your data.
Data controller within the meaning of the GDPR:
VisionByte | Digital Agency (sole proprietorship)
Owner: Alexander Wörl
Astheimer Str. 31
65428 Rüsselsheim am Main
E-Mail: privacy@braincell.me
Branch (dependent establishment):
Bahnhofsplatz 1
65428 Rüsselsheim am Main
When you register for a user account, we collect your email address and a password of your choice in order to set up your account and to uniquely authenticate you when you use the app. The legal basis for this is Art. 6 (1) lit. b GDPR (performance of a contract).
To optimize the learning functions of our app, we store and process data about your learning progress, such as answer history, flashcards used, ratings, and timestamps. This enables us to offer you personalized learning recommendations and optimized repetition intervals. The processing is based on our legitimate interest pursuant to Art. 6 para. 1 lit. f GDPR.
In order to prevent fraud and to deliver push notifications, we collect data about your device (device ID, operating system version, push token). The legal basis is also Art. 6 para. 1 lit. f GDPR.
Payments for premium subscriptions are processed exclusively via the Apple and Google app stores. We do not process payment data directly, but only receive transaction information for verification purposes. The legal basis is Art. 6 (1) lit. b GDPR.
We use the Supabase service, hosted within the EU, to store your data securely. Data is transmitted using TLS encryption and stored in accordance with modern security standards. Supabase processes data exclusively on behalf of and on the basis of a data processing agreement in accordance with Art. 28 GDPR.
We use WishKit to receive feedback and feature suggestions. Only data that you voluntarily provide via the feedback form and anonymized usage statistics are processed. The basis for this is our legitimate interest pursuant to Art. 6 (1) lit. f GDPR.
We use an external AI service for the AI-based creation of index cards. This involves processing the text you enter (prompts) and the generated results. The service provider has been carefully selected, meets the requirements of the GDPR, and processes data either within the EU, on the basis of standard contractual clauses, or under the EU-US Data Privacy Framework. The legal basis is Art. 6 para. 1 lit. b GDPR.
We do not sell personal data to third parties. Data is only disclosed to the external service providers mentioned above if this is necessary for the fulfillment of the contract, for the fulfillment of legal obligations or on the basis of legitimate interests.
Personal data will be deleted as soon as the purpose of processing no longer applies or you delete your user account. This does not apply to data for which statutory retention periods exist (e.g., commercial or tax law requirements).
To protect your personal data from loss, destruction, or unauthorized access, we use technical and organizational measures in accordance with current security standards. Data transfers are exclusively encrypted (TLS), and stored data is hashed or encrypted according to established procedures.
You have the right at any time to:
To exercise your rights, please contact privacy@braincell.me.
You also have the right to lodge a complaint with a data protection supervisory authority. The Hessian Commissioner for Data Protection and Freedom of Information is responsible for this.
We reserve the right to update this privacy policy as necessary, for example if we change our services or to comply with new legal requirements. You can view the current version at any time in the app under "Privacy" or on our website.
This privacy policy is clearly published in accordance with Apple and Google guidelines, both in the app and in the store listings, in order to comply with all relevant guidelines.