This is a plain-language summary for the beta. Last updated: October 16, 2026.
Your books, reading progress, saved words, flashcard schedule and settings are stored in your browser. We don't receive them. Clearing your browser data erases them. You can also remove books and saved words inside the app, or use Delete all my data in Settings.
When you tap a word, the word, a short passage around it (up to about 500 characters), and your language and detail settings are sent to our server, which forwards them to Anthropic's Claude API to produce the explanation. Our code does not store this text. Anthropic's own terms and privacy policy apply to how it handles API requests, and our hosting provider (Cloudflare) may keep standard technical logs such as IP addresses. To limit abuse, our server briefly counts lookups per IP address in memory.
The reader loads a small library for opening EPUB files from Cloudflare\u2019s CDN (cdnjs.cloudflare.com). The pronunciation button uses your browser\u2019s built-in speech voices, which your browser or device may process online.
There are no accounts and no payments in this beta.
Explanations are generated by an AI model and can be wrong.