Telegram is a messaging application that is focused on speed. It is fast, simple to use and free. Telegram is based on the MTProto protocol. With Telegram, you have the option to create group chats with up to 200 people. You can share videos up to 1GB is size, you can send multiple photos from the web, and you can also forward any media you receive instantly. As all your messages are held in the cloud, you can easily access them from any of your devices that are connected.
Key features include: Fast: Telegram uses a decentralized infrastructure with data centers positioned globally. Cloud Storage: Telegram offers free unlimited cloud storage for all your Telegram messages and media that you can securely access from multiple devices. Group chat: You can form large group chats up to 200 members, and quickly share videos up to 1GB. Reliable: Telegram delivers your messages in the minimum bytes possible. 100% Free with no ads: Telegram is free and will always be free. Privacy: Telegram takes privacy very seriously and promises to never give third parties access to your data! Overall, Telegram is an easy to use messaging application that has robust security, a simple user interface and provides a rapid service with speed not entirely dependent upon your device specification. (Source: filehippo)