Privacy

We store the minimum needed to run the app: your email (sign-in), the name you give your samurai, the cards and decks you use, your study history, and your streak. We do not sell or share this data.

When you sign in with Google, we receive your email and profile photo from Google. When you sign in with email magic link, we send a one-time link via Resend.

Audio playback uses Google Cloud Text-to-Speech; the resulting audio files are stored on Vercel Blob and served back to you. AI-generated card content (definitions, examples, translations, illustrations) is produced by Cloudflare Workers AI and stored on Vercel Blob the same way.

With your consent, we use Sentry to capture crashes and a brief replay of the error (no passwords, no email, no auth headers — see the consent banner for what each category covers). We use PostHog for anonymous funnel analytics — keyed by an internal user id, not your email or name. You can change either choice at any time from Self → Cookie preferences.

You can delete your account at any time from Self. Deletion is immediate and cascades to every record we keep about you.

Questions: contact@kotoba.dojo