Privacy

If you don't sign in, EverFlip stores your study progress in your browser's localStorage — it stays on your device and there is no account. We do still collect anonymous usage analytics (see below) to improve the product.

If you sign in with Google, we store the following on our server so your progress survives across devices and browser cache clears:

• Your Google account email, display name, and profile picture URL
• Your spaced-repetition state per card (due date, difficulty, stability, review history)
• Your daily counters (new cards introduced today, review limit, etc.)
• If you create child profiles, their names, ages, avatars, and per-language card progress
• If you create custom decks, the deck names, descriptions, card content, and your display preferences
• Which built-in decks you've chosen to hide
• If you request a deck review, Arthur (admin) sees that deck's contents and your email until the request is completed

We do not use advertising trackers, and we do not sell or share your data.

Anonymous counts

To learn which languages people want — so we know which courses to build out next — we keep a few anonymous tallies: how many times a language was started, how many home visits there were, and how many people signed in, each per day. These are plain numbers ("Swahili started 42 times today"). They carry no account id, no IP, no cookie, and no session — nothing that can be tied back to you, signed in or not.

Usage analytics

To understand how EverFlip is used and where it can improve, we use two analytics services: Google Analytics 4 (traffic and where visitors arrive from) and PostHog (how features are used — which study flows people complete, where they drop off, plus anonymized session replays to spot confusing UI). These use cookies and collect usage data such as pages viewed, clicks, device and browser type, and a coarse location derived from your IP address. We use this to improve the product, never to advertise to you, and we never sell it. PostHog session replays mask all text you type.

Where it lives

Authentication runs through Auth.js (NextAuth) with Google as the only provider. User data is stored in a managed PostgreSQL database (Neon). The database is hosted in the EU.

How to delete your data

Use the contact form and we'll wipe your account and all associated card state within a few days. You can also revoke EverFlip's access from your Google account permissions page.

No ads, ever

There are no ad networks on EverFlip — the analytics above exist to improve the product, not to sell ads or build a profile to target you with. Your study progress lives in your browser (and, only if you sign in, in your own synced account).

Last updated: 2026-06-10.