Five Mistakes to Avoid When Developing Telegram Mini Apps

Сontents

Performance Issues
Poor User Interface (UI/UX)
Misalignment with User Expectations
Lack of Integration with Telegram API
Security Issues
Conclusion

Developing Telegram Mini Apps is a great way to create a convenient service inside the messenger. However, like any other development process, it’s easy to make mistakes that can harm the user experience, reduce performance, or cause the Mini App to be underused. In this article, we’ll explore five key mistakes to avoid when creating a Telegram Mini App and provide recommendations on how to prevent them.

Performance Issues

Mistake: Slow load times and lagging

Mini Apps need to load quickly—Telegram users are used to instant access to content. If the Mini App takes longer than 2–3 seconds to load, there’s a high chance the user will simply close it.

Causes of poor performance:

Unoptimized code with too many heavy scripts.
Too many HTTP requests to the server.
Large images and resources (e.g., not using compression).
Server issues like slow databases or overloaded backends.

How to fix it:

Minimize and compress code (use Webpack, Terser).
Optimize images (use WebP, SVG formats).
Implement caching on both the client and server sides.
Set up a CDN for faster resource loading.
Profile the app using tools like Chrome DevTools.

Poor User Interface (UI/UX)

Mistake: Complicated or cluttered interface

Telegram Mini Apps need to be simple and intuitive. If the interface is too complex, overloaded with buttons, or confusing, users won’t want to engage with it.

Typical UI/UX errors:

Unclear navigation (the user doesn’t know where to click).
Overloaded interface (too many buttons or too much information).
Unresponsive design (the Mini App doesn’t adapt to mobile screens).
Ignoring Telegram’s theme (not considering light/dark mode).

How to fix it:

Use a minimalist interface, showing only the essential information.
Test with real users and gather feedback.
Add support for dark mode (Telegram.WebApp.colorScheme).
Consider screen size and make interactive elements easy to click.
Use Telegram UI components (e.g., Telegram.WebApp.MainButton).

Example code for adapting to dark mode:


javascript

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const bgColor = Telegram.WebApp.colorScheme === "dark" ? "#1c1c1c" : "#ffffff";
document.body.style.backgroundColor = bgColor;

Misalignment with User Expectations

Mistake: The Mini App doesn’t do what users expect it to

A common mistake is creating a Mini App without fully understanding the users’ needs. For instance, if the app is too complicated, requires unnecessary steps, or simply doesn’t solve a real problem, users will be disappointed.

Typical issues:

The features of the Mini App don’t meet users’ expectations.
The user has to manually input data that can be automatically retrieved via Telegram API.
The app feels like a website rather than a part of Telegram.

How to fix it:

Analyze your users: Find out what they really need.
Use Telegram.WebApp.initDataUnsafe to auto-fill data.
Keep the Mini App simple—focus on 1–2 key tasks.
Ensure smooth integration with Telegram, such as using inline buttons.

Example code to automatically retrieve the user’s name:


javascript

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const user = Telegram.WebApp.initDataUnsafe.user;
document.getElementById("username").innerText = `Привет, ${user.first_name}!`;

Lack of Integration with Telegram API

Mistake: Mini App doesn’t leverage Telegram’s features

One of the main advantages of Telegram Mini Apps is their deep integration with the messenger. However, many developers create basic web apps and miss out on key Telegram features.

Features often ignored:

Authorization via Telegram (initDataUnsafe).
Using the Web Apps API to manage the interface.
Sending data back to the bot (sendData).
Using Telegram Payments for monetization.

How to fix it:

Enable Telegram API-based authorization so users don’t have to manually enter their information.
Use the Bot API to send messages to users.
Integrate Telegram Payments if you plan to monetize.
Use the Telegram.WebApp.MainButton for smooth user interaction.

Example code to send data to the bot:


javascript

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Telegram.WebApp.sendData(JSON.stringify({ action: "buy", item: "premium" }));

Security Issues

Mistake: Vulnerabilities in code and data leaks

Since Mini Apps run in the Telegram browser, developers often underestimate security concerns. For example, improper handling of data can lead to unauthorized access to user accounts.

Key security mistakes:

Using HTTP instead of HTTPS for data transmission.
Using insecure tokens without validation.
Unrestricted requests to the server (leading to DDoS attacks).
Not sanitizing user input (XSS, SQL injections).

How to fix it:

Always use HTTPS for loading the Mini App.
Validate Telegram tokens before processing data.
Implement rate limiting to control server requests.
Filter input data in all forms to prevent security breaches.

Example code to validate a Telegram token (Python):


python

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import hashlib
import hmac

def check_telegram_auth(data, token):
    secret_key = hashlib.sha256(token.encode()).digest()
    check_string = "\n".join([f"{k}={v}" for k, v in sorted(data.items())])
    hmac_hash = hmac.new(secret_key, check_string.encode(), hashlib.sha256).hexdigest()
    return hmac_hash == data.get("hash")