Privacy Policy
Last updated: May 27, 2026
Lexisy is a vocabulary learning tool offered as an Android app and browser extension. This page describes what we collect and your choices.
What we collect
Account information
When you sign in via Firebase Authentication, we receive your email address. Your password is hashed by Firebase; we never see it.
Your vocabulary data
If you enable cloud backup, your favorites, lookup history, familiarity ratings, quiz answers, and premium status are stored in Google Firestore scoped to your Firebase user ID.
Selected text
When you use Lexisy to look up or translate text, it is first queried against the offline dictionary on your device. If not found, it may be sent to a third-party translation service for a fallback result.
What we do not collect
- No analytics SDK or advertising trackers.
- No device identifiers, IP addresses, or location data.
- No access to your contacts, photos, microphone, camera, or files.
- We do not sell or rent your data.
Third-party services
Lexisy uses:
- Firebase (Google) — Authentication and Firestore. See Google's Privacy Policy.
- Translation services — Fallback translations for text not in the offline dictionary.
- GitHub Releases — Dictionary file hosting. No user data sent.
Data retention and deletion
Delete your account from the Account screen to remove your Firestore data and Firebase record. Offline data can be cleared by uninstalling the app or clearing extension storage.
Security
- All network traffic uses HTTPS.
- Firestore data is access-controlled per user ID.
Contact
Questions? Email hi@lexisy.com.