Even as a Viber user I find it strange that it took off. Most phone plans here come with unlimited texts and basically unlimited calls. Most people are also on Facebook which has a great messenger app. And yet my friends use Viber (which means I have to). And every time I ask them why, their reasoning is free calls. Most of these people have unlimited minutes. Not only is this strange but annoying as to contact them I now have to send my communications through yet another company.