There seems to be an infinite number of self-destructing apps that promises secure messaging, but Telegram is adding another benefit to its free service – it’s a nonprofit company with an open source model. There are no ads and will never be, plus, anyone can download the sourcecode and read how Telegram works – it’s all available on Github.
You can use Telegram to send cloud-based messages as well, they’re just not going to be secured:
The makers of Telegram are also working on encrypted voice calls, but at this time, you can only send texts, images, and videos. Compared to Snapchat, Telegram will allow you to have a group chat with up to 100 users. Keep in mind that your contacts will also need Telegram in order to receive messages.