http://www.viber.com/ Viber is an application for iPhone®, Android™, Windows Phone and Blackberry phones that lets you make free phone calls to anyone that also has the application installed.
When you use Viber, calls and text messages to any other Viber user are free, and the sound quality is much better than a regular call. You can call or text any Viber user, anywhere in the world, for free. All Viber features are 100% FREE and do not require any additional "in application" purchase.
