Viber

App Name: Viber Price: Free Available Platforms: Windows, Mac, IOS, Android, Windows Phone, Blackberry, Nokia, and Bada

What does this app do?: With over 200 million users and a recent update to its mobile app including an overhaul to the Android interface, Viber has lot to offer these days. The app allows users to communicate with other Viber users via text message and voice calling.

For free.

The application, which requires a 3G or Wi-Fi network, functions ideally for travelers and those who want to avoid roaming charges. For instance, say you need to be in London for a business meeting, or you're vacationing in Italy and want to make a call or send a message to a colleagues or a family member. Once you download the app, it scans your address book and displays those who also use the app in its contact list. From there, you can place a call or send a message for free. (If the person you want to reach doesn't have the application, your mobile service provider will place the call).

Along with the most recent update to its mobile app, Viber also released a version for Windows and Mac desktops giving users the ability to integrate their contacts and transfer calls and messages between devices allowing you to effortlessly switch from your mobile phone to your desktop and back again.

For the moment, the company offers video messaging through the desktop application, too, but hasn't yet released the feature for mobile devices.

Is it easy to setup: Yes. Download the app, and make sure you enable notifications. Once you provide your phone number, Viber will send you a pin number for you to enter and from there the app automatically syncs other Viber users in your contacts list. If you're using the desktop application, you will need to download the app, too, in order to get started.

Should I try it?: Viber proves handy for those who want to save money, especially on international calls. A few years ago, Skype was the go-to free voice and message applications, and while that remains widely used, Viber has gained momentum; with an impressive list of supported languages, platforms and devices as well as a growing numbers of downloads, the app is soon to be ubiquitous.