Telegram is a cloud-based messaging app for phones and desktop computers, with a focus on speed and security. It is supported by Pavel Durov and his brother Nikolai, who developed its custom data protocol, and its development team is based in Dubai. Telegram reports more than 1 billion active users.
Because messages are stored in Telegram's cloud, they sync across all of a user's phones, tablets and computers at the same time. A user can send messages, photos, videos and files of any type up to 2 GB each, create groups of up to 200,000 members, and run channels that broadcast to unlimited audiences. Cloud chats use server-client encryption; optional Secret Chats add client-to-client (end-to-end) encryption and self-destructing messages. Telegram has an open API and publishes source code, and its Bot API lets developers build programs that act inside chats.
Private messaging is free, with no ads or subscription fees. Telegram Premium is an optional subscription that adds features such as 4 GB uploads, faster downloads and voice-to-text conversion.