It’s not immediately clear why Telegram emerged as the alternative of choice following WhatsApp’s downtime. Users could have switched to Kik, or Facebook Messenger, or LINE — all of which have hundreds of millions of users. There’s seemingly something different about Telegram. Its rise isn’t only due to WhatsApp’s acquisition and subsequent downtime. "We have been the no. 1 app in Spanish, Arabic, and several Latin American app stores for several weeks before the Facebook deal happened," says Telegram's Markus Ra. "The growth was there — so the WhatsApp acquisition and problems merely multiplied the effect across all affected countries." According to app analytics site App Annie, Telegram started truly gaining steam on February 17th, days before the WhatsApp news even hit.
Telegram feels in many ways like a straight-up clone of WhatsApp, from its green double-checkmark read receipts to its cartoonish wallpapers. There’s also the usual gamut of messaging app features including the ability to see a friend's online status and attach photos, videos, your location, contacts, and documents to messages. But where it lacks originality, Telegram makes up for it in speed and security features. "Telegram is the fastest and most secure mass market messaging system in the world," the company claims, which it attributes in part to Nikolai Durov’s open-sourced MTProto protocol. Telegram was in fact built as a testing bed for MTProto, Reuters reported when the app launched back in August. The company is so confident in the security of MTProto that it’soffering $200,000 to anyone who can crack it. It’s not unusual for companies to offer bug bounties, but bounties of this size are generally only reserved for critical bugs in widely used apps like Windows.
There is a big critic is that ,the ISIS terrorist from the last paris attach using the same telegram applications for communication. Now Telegram officials introducing a new feature ‘Super Group’. Now the maximum number of members is 100 in a watsapp group. But the telegram groups having 200 as a limit. The super group have the maximum members as 1000. We can update the telegram groups in to super group that means we can add 1000 members to that group.