Telegram Mini Apps are the highest-leverage distribution channel in crypto right now. A billion monthly users, no app store review, and a share button that works. Here is how to actually build one.
1. Understand what a Mini App really is
A Mini App is a web page rendered inside Telegram's in-app browser with a JavaScript bridge to Telegram-specific APIs. That is it. If you can build a React app, you can build a Mini App — the difference is entirely in how you handle identity and payments.
2. Validate initData on the server. Always.
When Telegram opens your app it passes an initData string containing the user object and a hash. The single most common security failure I see is trusting the user ID from that string on the client.
You must recompute the HMAC on your server using your bot token as the key and compare it to the provided hash. If they do not match, reject the request. If you skip this, anyone can open your API with a forged user ID and drain whatever balance system you built.
3. Design for the viewport, not the desktop
Mini Apps open in a sheet that users can drag down to close. Use expand() immediately, disable vertical swipe closing if your app scrolls, and account for the safe area at the bottom. Test on a real device — the desktop client lies to you about sizing.
4. Payments: Stars, TON, or both
Telegram Stars work for digital goods and take a platform cut. TON Connect gives you real crypto payments with no cut but adds wallet friction. Most successful apps offer both: Stars for impulse purchases, TON for larger amounts.
5. What gets apps banned
Aggressive forced-referral gates, misleading earnings claims, and anything resembling gambling without proper handling. Telegram enforces unevenly but permanently. Keep referral rewards genuine and never promise token value.
6. Ship it
Deploy the frontend anywhere with HTTPS, point BotFather at the URL, and you are live. No review queue, no waiting.
If you want the whole thing pre-built, the Tap-to-Earn Mini App source code covers every point above in production code.
