This is a legit and common question. For now, Viber's focus is on adding platforms, adding features and improving overall system performance.  At the same time, we are working on additional future premium services that will generate revenues. The basic Viber service - Viber to Viber text messages - will ALWAYS be free. 

Rest assured that Viber will NEVER spam, rent, or sell user information. For more information concerning this, please see our privacy policy at: http://www.viber.com/privacypolicy.html

Stay tuned!
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