Grand Sumo Tournament (“we”, “us”) operates the website grandsumotournament.com and the Grand Sumo Tournament mobile app (together, the “Service”). This Privacy Policy explains what information we collect, how we use it, and your choices.

By using the Service, you agree to this policy. If you do not agree, please do not use the Service.

We collect only the information needed to provide tournament data, optional accounts, and paid predictions.

• Account information: if you create an account in the mobile app, we store your email address and authentication data through Supabase Auth.
• Subscription status: if you subscribe to predictions, Google Play or the Apple App Store processes payment. RevenueCat tells us whether your account has an active subscription so we can unlock predictions.
• App preferences: when signed in, no-spoiler mode is saved to your account and syncs across devices. Other display preferences may be stored locally on your device.
• Usage data: when you use the Service, our servers receive standard request data such as IP address, device type, and pages or API endpoints accessed.
• Website analytics: the website uses privacy-focused analytics (Umami and Cloudflare Web Analytics) to understand traffic and improve the site. The mobile app does not use these tools.

• Provide tournament data, standings, banzuke, and match results.
• Authenticate users and manage optional sign-in.
• Verify subscription status for paid match predictions.
• Operate, secure, and improve the Service.
• Respond to support requests.

We use trusted providers to run the Service. They process data only as needed to provide their services to us:

• Supabase — authentication and database hosting.
• RevenueCat — subscription management.
• Google Play / Apple App Store — in-app purchases and billing.
• Cloudflare — website and API hosting, plus privacy-focused Web Analytics.
• Umami — privacy-focused website analytics.

Paid predictions are statistical win-probability estimates based on ELO ratings, head-to-head records, and current tournament performance. They are for informational and entertainment purposes only. They are not betting advice, gambling services, or financial guidance.

We keep account and subscription records while your account is active and as needed to comply with legal obligations, resolve disputes, and enforce our terms. Local app preferences remain on your device until you clear app data or uninstall the app.

• You can use most of the Service without creating an account.
• You can sign out of the mobile app at any time from Settings.
• You can manage or cancel subscriptions through Google Play or the Apple App Store.
• You may request access to or deletion of your account data by contacting us.
• To delete your account, follow the steps on our Delete Account page.

The Service is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has provided us personal information, please contact us so we can delete it.

We may update this Privacy Policy from time to time. We will post the updated version on this page and change the “Last updated” date above. Continued use of the Service after changes means you accept the updated policy.