Telegram's Bot API is one of the most accessible messaging APIs available to developers. Unlike platforms that require lengthy approval processes or partnership agreements, Telegram lets anyone create a bot in under a minute and start sending messages programmatically. For app developers, this opens up practical possibilities ranging from notification delivery and monitoring to full conversational interfaces.
Whether you want to forward alerts from an Android app to a Telegram chat, build a customer support channel, or create an automated reporting system, the Bot API provides the foundation. This guide covers the essentials of getting started.
Creating a Bot with BotFather
Every Telegram bot starts with BotFather, which is itself a bot. Open Telegram, search for BotFather, and start a conversation. The command to create a new bot is straightforward: send the message /newbot and follow the prompts.
BotFather will ask you for two things: a display name for your bot (which can include spaces and does not need to be unique) and a username (which must be unique across all of Telegram and must end with the word "bot"). Once you provide both, BotFather generates an API token, a long string of characters that serves as your bot's authentication credential for all API calls.
Guard this token carefully. Anyone who has it can control your bot, send messages as the bot, and access any data the bot receives. If your token is ever compromised, you can revoke it through BotFather and generate a new one.
BotFather also lets you configure your bot's profile picture, description, about text, and command list. Setting up a proper command list is particularly useful because Telegram displays these commands as suggestions when users type a forward slash in the chat with your bot.
Sending Your First Message
The Bot API is a standard HTTP API. You make requests to endpoints at api.telegram.org, passing your bot token and the required parameters. The simplest and most common operation is sending a text message.
To send a message, you need the bot token and the chat ID of the recipient. The chat ID is a numeric identifier for a user, group, or channel. For personal messages, each Telegram user has a unique chat ID. For groups, the chat ID is assigned when the group is created. You can discover chat IDs by having users send a message to your bot and reading the incoming update data.
The API supports rich formatting options. You can send messages with Markdown or HTML formatting, include inline keyboards with clickable buttons, attach images and documents, and send location data. Inline keyboards are particularly powerful because they allow users to interact with your bot through button taps rather than typing text, creating a more app-like experience within the Telegram interface.
Receiving Messages: Polling vs Webhooks
Sending messages is only half of the equation. To build an interactive bot, you also need to receive messages and events from users. Telegram provides two mechanisms for this: long polling and webhooks.
Long polling is the simpler approach. Your application periodically calls the getUpdates endpoint, which returns any new messages or events since the last call. If there are no new updates, the request blocks for up to a configurable timeout (up to 50 seconds) before returning an empty response. This approach requires no server infrastructure beyond the ability to make outbound HTTP requests. It works behind firewalls and NATs without any special configuration.
Webhooks are more efficient for production deployments. Instead of your application polling Telegram's servers, you register a URL with Telegram, and Telegram sends updates to that URL as they arrive. This eliminates the latency of polling intervals and reduces unnecessary network traffic. The tradeoff is that your server must be publicly accessible over HTTPS with a valid SSL certificate.
For mobile apps that integrate with Telegram bots, the choice often depends on architecture. If the bot logic runs on a server, webhooks are the standard choice. If the bot logic runs directly on an Android device, long polling is more practical since phones typically do not have public IP addresses or run web servers.
Practical Bot Patterns for App Developers
The most common use of the Bot API in the context of mobile apps is notification delivery. An Android app can use a Telegram bot to send alerts, status updates, and reports to the user's Telegram account. This is useful because Telegram notifications are reliable, cross-platform, and free. Unlike email, which might land in a spam folder, or SMS, which costs money per message, Telegram messages arrive instantly and are visible across all of the user's devices.
Another pattern is using a Telegram group as a lightweight logging or monitoring channel. An app can send structured messages to a private group whenever certain events occur: a motion sensor triggers, a backup completes, an error threshold is exceeded. The group serves as a persistent, searchable log that is accessible from any device.
Bots can also serve as remote control interfaces. By defining a set of commands, you can interact with your app or server from Telegram. Sending /status might return system health metrics. Sending /restart might trigger an app restart. This is particularly useful for headless applications or devices that do not have a traditional user interface.
Rate Limits and Best Practices
Telegram enforces rate limits to prevent abuse. Bots can send up to 30 messages per second to different chats, but only one message per second to the same chat. For group chats, the limit is 20 messages per minute. Exceeding these limits results in 429 (Too Many Requests) errors with a retry-after header indicating how long to wait.
Design your bot to respect these limits. If you need to send notifications to many users, implement a queue with rate limiting rather than firing all messages simultaneously. Batch non-urgent notifications and spread them over time.
Handle errors gracefully. Users can block your bot, leave groups, or delete their accounts. When the API returns a 403 (Forbidden) error, stop trying to send messages to that chat. Persisting in sending to blocked or deleted chats wastes API quota and can trigger additional restrictions on your bot.
Keep your bot token out of source code repositories. Use environment variables or a secure configuration system to store credentials. A token committed to a public GitHub repository will be discovered and abused within hours. If one practical use case appeals to you right away, TeleSMS is an Android app that connects to your Telegram bot to automatically forward SMS messages based on customizable filters, delivering them to your chosen chat in real time.