When you use Viber, your phone calls to any other Viber user are free. You can call any Viber user, anywhere in the world, for free. All Viber features are 100% FREE and do not require any additional “in application” purchase.
Both you and your contacts must have the application . If you do, then you are all set. You will get the call at no cost, and on top of that the sound will be really crisp.
CALL ANYONE WITH VIBER, NOT JUST YOUR FRIENDS: Want to dial a number and don’t know if they have Viber? No problem, make the call with Viber and if they don’t have Viber the call will be made using your regular phone – but don’t forget to invite your friends to Viber so your next call is free.
Viber behaves just like a phone. Just like you do not need to “add” someone in order to call them, you do not need to add your friends in order to call them on Viber. If you know their phone number, then you know their Viber number, and you’re ready to go!
Soon to hit the Android Market and Free SMS coming soon too.