Yes you can. It requires the BlackBerry OS 5.0 or higher and it is currently in its beta version. ”Beta” actually means that you cannot enjoy the HD sound quality the way both iPhone and Android users can. Remember – you cannot make calls with this version! However, the beta version does include the other two significant features: text and photo messages, as well as address book synchronization.
You can install it by browsing the BlackBerry App World or by clicking on this link http://viber.com/blackberry.