Telegram is an easy-to-use, secure messaging and VoIP service. The program can be installed on multiple locations and devices, and will synchronize with all connected tools. It supports video calls, broadcast messages, huge chat rooms and can transfer any file type, up to 1.5 gigs each.
Note the program requires a working phone number in order to log in (via SMS or automated phone call).
Cross-platform with clients available for Mac, Linux, iOS, Android and as a web app. A PortableApps version is also available.
