Privacy policy

Last updated: 28 October 2026

Goukaku is a study app. It does not show ads, does not sell your data and does not include any analytics or tracking library. This page lists what is collected and where it goes.

Stays on your phone

Your study history, spaced-repetition schedule, streaks, settings, Listening progress and downloaded files are stored only on your phone. We never receive them. If you uninstall the app or clear its storage, they are gone.

Your Google account

If you sign in, you do it with Google through Clerk, our sign-in provider. We store your email address and an account id so we can match a Premium purchase to you. Your Google password is never seen by us or by the app.

Setup answers

When you first open the app it asks your level, the month of your exam, how many new cards you want per day and how you found the app. These answers are sent with a random install id (not your name or phone number) so we can see roughly who uses the app. If you sign in, the install id is linked to your account.

Feedback and card reports

If you send feedback or report a mistake on a card, we receive what you typed, an optional email you chose to give, the install id, the app and Android version, and for a card report the card's content and the reasons you picked.

Premium records

When you buy Premium or redeem a code we keep a record of the email, the plan, the dates and how it was paid, so we can switch Premium on and off correctly and answer questions about it. We do not collect card or bank details: payment happens in chat, outside the app.

Who handles the data

We use a few services to run Goukaku: Clerk (sign-in), Vercel and Neon (the server and its database), Cloudflare (this website, relaying the app's requests and hosting audio files), Expo (delivering app updates) and UploadThing (hosting the APK file). Because some networks block these services, requests may pass through Cloudflare on the way. These providers process data only to provide their service.

This website

This website has no cookies, no analytics and no ads. Like any web server, the hosting provider may keep ordinary technical logs such as IP address and time of request.

Your choices

You can use the free content without signing in. You can ask us to delete your account records, setup answers and reports by contacting us below; we will delete what we can link to you, keeping only what we must for an unfinished purchase.

Changes

If what we collect changes, we will update this page and the date above.