A few requirements for full functionality:
Viber for iOSiPhone 4 and later
iPhone and iPads with iOS 7.0 and above
2.3.6 and above
Viber for Android
Windows Phone 8
Viber for Windows Phone
Minimum 512 MB RAM is required.
Delay in call notifications may occur. Issue resolution is in progress in cooperation with Microsoft.
Viber for Blackberry
Only full-touch devices running BlackBerry version 10.2.1 and later are supported
*Note: Blackberry store might disable some devices that do meet the above requirements.
(Viber for Desktop can be installed only after the most recent version of the application has been installed on a mobile device)
Viber for Desktop*
Windows: 7, 8, 10, XP SP3, Vista
Mac: OSX 10.7 and above
Linux: Ubuntu 64 bit, Fedora
Windows 8 Desktop Application Important Information:
After upgrading your primary device to Viber version 6.0, the Windows 8 desktop Viber app will no longer be supported. However, you can still download and activate Viber for Desktop.
*Minimum hardware requirements:
CPU: Dual core processor
Microphone and speakers for voice calls and webcam for video calls
AD2P compatible Bluetooth receiver for BT devices