Last updated: February 2026

The short version

Grinn is designed with privacy at its core. Your smile data stays on your device. We don't collect photos, videos, or biometric data. The camera is used solely for real-time smile detection and nothing is stored or transmitted.

What we collect

Anonymous analytics: We use Firebase Analytics to understand app usage patterns (e.g., which features are popular). This data is anonymized and cannot identify you.
Push notification tokens: If you enable reminders, we store a device token to deliver notifications. This is not linked to your identity.
Purchase data: Subscription management is handled by RevenueCat. We do not store your payment information directly.

What we don't collect

Photos or videos from your camera
Biometric or facial recognition data
Your name, email, or any personal account information
Location data

Data storage

All your app data (streaks, preferences, journal entries) is stored locally on your device using Hive, an encrypted local database. If you delete the app, your data is permanently removed.

Third-party services

Firebase (Google): Anonymous analytics and push notifications
RevenueCat: Subscription management
Google ML Kit: On-device face detection (no data leaves your device)

Contact

Questions about privacy? Reach us at hello@grinnapp.com