retane1. Information we handle
We handle your authentication user ID; email address, display name and profile photo provided through Google sign-in; cards, decks, review history, study days and settings; purchase status; and AI usage records. Contact inquiries include the information you enter into the form.
Study data is stored on your device. Once linked to Google, it is eligible for synchronization and backup using Firebase Firestore. Exported backups also remain wherever you save them.
2. How information is used
Information is used for authentication, saving and restoring study data, AI features, purchases and usage allowances, abuse prevention, troubleshooting, understanding usage and responding to inquiries.
3. Text, images and audio
AI features send your input text and images, or relevant card content, to OpenAI through a Cloudflare Worker. Microphone recordings are sent through the same route for transcription after recording stops.
The AI proxy does not implement ongoing storage of the submitted text, images or audio themselves. This does not mean that temporary processing data, provider logs or retention, and device caches never remain. Native recordings may remain in temporary files on the device.
OpenAI API data is not used for model training by default. Retention for purposes such as abuse monitoring varies by API, contract and settings.
4. External services and payments
Google / Firebase provides authentication, study data synchronization and backups, and analytics. Google Forms handles inquiries. Cloudflare delivers the sites, proxies AI requests and handles usage limits and operational records. OpenAI provides card assistance and transcription.
Your user ID is shared with RevenueCat to manage purchases and subscriptions. Web payments use Stripe. Payment details are handled by the checkout provider; complete payment card numbers are not stored in retane's study database.
Depending on these providers' processing locations, information may be processed and stored outside Japan.
5. Usage records, cookies and similar storage
Server-side AI usage records include user ID, model, plan, time, result, request counts, token usage and audio file size. Premium status and expiration are also checked.
The app includes Firebase Analytics for screen transitions, device information and usage events. Authentication, study data, settings and analytics may use cookies or browser storage. Native apps initialize the Google Mobile Ads SDK; the Web app does not use this advertising SDK.
The Web image editor loads a library from cdnjs. This separate policy site adds no independent analytics tags, advertising tags or sign-in features, but its hosting provider may keep connection and security records.
6. Retention and deletion
The app does not set a uniform automatic deletion period for study data or AI usage records. Retention depends on card or account deletion and providers' settings and policies. Older backups and temporary device files may retain information.
When My Page account deletion completes successfully, it deletes the targeted Firestore data and cloud backups, the device's cards, decks, study history and relevant settings, and the Firebase account. Network failures may leave some steps incomplete.
This action does not collectively delete RevenueCat or Stripe transaction records, Cloudflare usage records, Analytics data, other devices' caches or your exported files. Provider backups and legal retention requirements can mean that a deletion request does not result in immediate complete erasure.
7. Privacy inquiries
Use the form below to ask about access, correction, deletion or restriction of your information, regardless of your Premium status.
Connections use HTTPS, and cloud study data is protected by user-ID-based access controls. Please also keep your devices and backup files secure.