Viber is an instant messaging and Voice over IP (VoIP) app for smartphones developed by Viber Media. In addition to instant messaging, users can exchange images, video and audio media messages. The client software is available for Mac OS, Android, BlackBerry OS, iOS, Series 40, Symbian, Bada, Windows Phone, and Microsoft Windows. A Linux version is available for Ubuntu 64-bit. Viber works on both 3G/4G and Wi-Fi networks. It first requires installation on a phone in order to work on a desktop operating system environment. Viber has over 100 million monthly active users from its 280 million global registered users.
The actual functionality varies from platform to platform with iOS and Android being the first to receive new features. Viber includes text, picture and video messaging across all platforms, with voice calling available only to iPhone, Android and Microsoft’s Windows Phone although HD voice is planned for Windows Phone 8. The application’s user interface includes tab bar on the bottom giving access to messages, recent calls, contact, the keypad and a button for accessing more options. Upon installation, it creates a user account using one’s phone number as username. Viber synchronizes with the phone’s address book, so users do not need to add contacts in a separate book. Since all users are registered with their phone number, the software returns all Viber users among one’s contacts. The newest version of Viber (Version 2.3) has added smileys and other default images.
Viber is also now available on Windows and Mac OS X.
As of December 2013, Viber officially launched Viber Out, a feature that provides users the option to call mobile and landline numbers; thus Viber users can call people not using a Viber app. Viber Out was originally released in November only to help Typhoon Haiyan victims in the Philippines connect with their loved ones. To use the new feature, users have to visit the “More” tab and choose Viber Out. No update is needed for the feature.