Legal & support
Privacy Policy
Last updated: 11 October 2026
This policy explains how MioCards handles information when you use the app.
Account and study data
Firebase Authentication creates an anonymous account and identifier so your library can sync without collecting an email address or phone number. If you choose to save your progress with Sign in with Apple or Google, Firebase Authentication links that provider to the same account and stores the provider identifier and the email address the provider shares (for Apple this may be a private relay address). The email is used only to sign you in to the same account on another device and is never used for marketing. Cloud Firestore stores your profile, sets, cards, review progress, and AI usage records. Cloud Functions processes app requests on the backend. Firebase Storage stores generated speech audio. These Firebase services are operated by Google.
AI card generation
When you request AI-generated cards, MioCards sends the topic and any instructions you provide to OpenAI through Cloud Functions, together with relevant language and set context. A one-way hashed identifier derived from your Firebase user identifier is supplied as a safety identifier. OpenAI returns draft card content for you to review.
Speech audio
When speech is generated, the text on the relevant card side is sent through Cloud Functions to AWS Polly. The generated audio is stored in Firebase Storage and may also be cached on your device so it can be played from the card.
Notifications
Your reminder preference and reminder time are saved locally. The notification schedule is created on your device after you grant notification permission. You can change the reminder in Settings and notification permission in iOS Settings.
Diagnostics and abuse prevention
In release builds, Firebase Crashlytics may process crash reports and related app, device, and operating-system diagnostics so reliability problems can be investigated. Firebase App Check may process app and device integrity signals and attestation tokens to protect Firebase backend services from abuse. MioCards does not use these services for cross-app or cross-site tracking or to serve advertising.
Service providers
MioCards uses Google Firebase for authentication, app data, backend functions, audio storage, crash diagnostics, and app integrity checks; OpenAI for requested AI card generation; and Amazon Web Services for Polly speech generation.
Account deletion
You can delete your account in Settings. The deletion flow removes the Firebase Authentication account and account-scoped data, removes account attribution from shared speech cache records, cancels the local reminder, clears local preferences, and clears the local library. A permanent hashed tombstone derived from the Firebase user identifier remains with deletion time and purpose metadata. It prevents late backend requests from recreating the deleted account and does not contain your study content.