The Use of Viber
Through Viber App, I can call those people and relatives so far away for free provided they have Viber too. So it a Viber to Viber case, you can send message for free all over different countries, you can also customized it by putting backgrounds to your Viber page.
So if you are not yet enjoying viber, check that application now and you will surely be happy you did it. As to my experience, I am satisfied in many ways.