Privacy policy (English)

Last updated: October 17, 2026. The Korean text above is the original.

Webcam

Hand tracking runs on your own device with Google MediaPipe. Camera video and hand coordinates are never sent to a server, recorded or stored. You can turn off camera access in your browser settings at any time.

Stored on this device

Your browser storage (localStorage) keeps your track times and stars, control settings, sound and language settings, and a random player ID and nickname. Clearing site data removes them.

Stored on our server

For the global ranking and community tracks we store on Supabase (Seoul data center): random player ID, nickname, track number, input type (hand/keyboard), time, nuts collected and timestamp; and for published tracks, the track code, name, layout, the author's player ID and nickname, and publish time. During 1v1 races your car position and nickname are relayed to your opponent in real time but not stored. We never ask for your real name, email or phone number. Please don't put personal details in your nickname.

We use Umami for privacy-friendly visitor statistics: pages visited, approximate country, browser and device type, and anonymous game usage counts such as starting with hands or finishing a track. It uses no cookies and does not identify you.

Ads and cookies

The game may show Google AdSense ads, only between races. Google and its partners may use cookies to show ads based on your visits to this and other sites. You can turn off personalized ads in Google Ad Settings; see also how Google uses information from partner sites.

Supporter codes

When you support the game on Ko-fi, Ko-fi sends us a notification (name, email, amount, transaction ID). We store the email and transaction ID with your supporter code so you can claim the code in Settings. The email is used only to find your code, never for marketing. Payments are handled entirely by Ko-fi.

Beta testing

If you turn on "Send anonymous control stats" in Settings, after each hand-controlled run we send numbers such as how often your hands were lost, tracking speed, your control settings, device type, browser and screen/camera resolution, together with your random player ID. Beta feedback includes your rating, selected issues, comment and the same summary numbers. No video, photos or hand coordinates are ever sent. You can turn this off at any time.

If you write a meaningful comment in your feedback, you get an ad-free code. To prevent repeat claims we store your random player ID and a one-way hash of your IP address with the code; the IP address itself is never stored.

Retention, children and contact

Ranking times and published tracks are kept while the service runs. To delete yours, contact us with your nickname and track code. Children under 14 should play with a parent or guardian. Contact: GitHub issues or Ko-fi.