Privacy Policy

77 Tennis (77tennis.com) is a free demo that I run personally. This page explains what I collect when you use it, why, and what you can do about it. When it says "I" or "me", that's the person running 77 Tennis.

What I collect

• Your email address. I use it to identify your account and to send you occasional updates about 77 Tennis. You can unsubscribe any time.
• Your nickname. It's the only name shown in the app, and your email is never shown publicly. Once you have at least 5 closed trades, your nickname and demo results (P&L, win rate, number of trades) appear on the public leaderboard. If you create a share link, anyone with that link can see your nickname and demo results on it. You can delete the link any time.
• Visitor statistics. For each page view I record which page it was, the referring website's domain (for example reddit.com), any campaign tags in the link (utm_source / utm_campaign) and an anonymous visitor code. The code is calculated from your IP address and browser together with a secret that changes every day and is then deleted. That lets me count daily visitors without cookies and without storing your IP address, and visits on different days can't be linked. Detailed records are deleted after 90 days and only daily totals are kept. There's no third-party analytics.
• Feedback you send. I keep the message, its type, the page you were on and your browser type. It's anonymous unless you choose to include your nickname, and I don't keep your IP address with it.
• Your password. It's stored only as a salted, one-way hash (argon2id). I can't see it or recover it.
• Demo trading activity. Your paper balance, positions, trade history (kept across resets) and take-profit / stop-loss settings. This is play money with no cash value.
• Consent records. When you agreed at sign-up, the exact wording you saw, and when you unsubscribed or re-subscribed.
• Technical data. A login session cookie, a security (anti-forgery) cookie, the time you were last active, whether you've seen the beginner intro, and your IP address for login and sign-up abuse protection (kept for at most 24 hours).

Your theme and layout preferences are stored only in your own browser.

Why I use it

• To provide your account and the demo (performance of my agreement with you).
• To keep the service secure and prevent abuse such as password guessing (legitimate interest).
• To understand how many people visit and where they come from, using the cookie-free statistics described above (legitimate interest).
• To send you occasional updates about 77 Tennis, such as the live version and new features. You agree to this when you create an account (consent). You can unsubscribe any time in Account settings or with the unsubscribe link in any email, and unsubscribing doesn't affect your account.

Cookies

I only use cookies that are strictly necessary: one keeps you logged in and one protects forms against forgery. There are no advertising or analytics cookies, and the visitor statistics work without cookies.

Sharing

I don't sell your data. My hosting provider (Hetzner, EU) stores it on my behalf. My email provider (Resend, EU region) sends the site's emails on my behalf: password resets, a welcome email and, unless you unsubscribe, occasional updates. Odds data comes from Polymarket. I don't send your personal data to Polymarket and I'm not affiliated with them.

How long I keep it

For as long as your account exists. When you delete your account, your email, password hash, demo trading data and consent records are deleted immediately. Security logs (IP-based attempt counters) are deleted automatically after 24 hours.

Your rights

You can access, correct or delete your data, and withdraw consent at any time. You can delete your account from Account settings → "Delete my account". For anything else, email me at hello@77tennis.com. If you're in the EU or UK, you can also complain to your data-protection authority.

Changes

If I change this policy I'll update this page, and I'll announce material changes on the site.