Although BlackBerry 10 devices can be sideloaded with the Android version of the messenger, a full-fledged Viber app is greatly anticipated by a lot of BB 10 users.
@kbuwa We are working with BB on a solution that will allow us to bring Viber to BB10. Please follow us for updates coming soon!— Viber (@Viber) March 2, 2014
Viber was recently purchased by Rakuten, a large Japanese e-commerce site, for roughly $900 million.
source: @Viber via BerryReview