Viber is one of the most popular applications on the iPhone that allows users to make free international calls and send text messages to other users using Viber 3G or Wi-Fi. After great success in Viber iPhone now heads to the Android platform. At this point Viber go through the process of beta testing and proven application of more than 20 Android devices. Viber Android app even lets you set as your default dialer Viber as we have seen in other applications of text messages, pop-ups receive a text each time it arrives. Calls are free, as long as the users are Viber others and these include cross-platform support means you can make free calls to your friends who have Viber iPhone on your phone. Watching video below explaining how Viber.