Telegram.Bot is the most popular .NET Client for Telegram Bot API. The Bot API is an HTTP-based interface created for developers keen on building bots for Telegram. Check Bots: An introduction for developers to understand what a Telegram bot is and what it can do. All Bot API methods are already documented by Telegram but this book covers all you need to know to create a chatbot in .NET.
A file chain system with Telegram as a storage. No limit to file size and format. It can be used as a telegram drawing bed or as a telegram net. Support web upload files and telegram upload directly.