In fact, the number of downloads of the Telegram app actually sent the app to the top 5 position in the App Store earlier today, where it also happened to be the no. 1 iPhone app across 48 different countries. Thanks to the three hour or so outage of WhatsApp, by the time it was Sunday afternoon, there were another 4.95 million that joined up with Telegram. The thing is, this huge and sudden influx of users (we are looking at 100 new users each second) has resulted in Telegram running into its own connection issues on the Old Continent, hence a 2-hour downtime. New servers were added to help alleviate the situation, but that would also have taken time. You can download Telegram for iOS and Android.