Viber is one of the social applications that is about to become extremely popular if the makers play their cards right. It’s been available on Android, Blackberry and iOS for a while now, and has just made its début on Windows Phone too.

The idea of the app is to allow people to connect with one another through phone calls and text message, wherever they are in the world, without paying a penny. You could have a Blackberry Curve or the brand new Samsung Galaxy S3 from Vodafone or O2, and so long as you have the app, communicate with your friends for free.

Of course both of you need to have the app in order for this to work. It’s just a download away though and so simple to use. How does it work? Well, it basically searches through your phone book on your behalf and finds everyone who has the app. It then syncs your phone so these contacts show up on the Viber app.

The reason it is so simple? Unlike with the likes of MSN and Twitter, You don’t need an email address to add a contact. It automatically locates the friends with it for you, which is much less hassle for you.

What does it mean? If you were to go on a holiday, and wanted to communicate with people back home for free, you can send a message or call someone through the app wherever you are in the world. No overseas charges. It’s a bit like Skype in that way. And you won’t end up with an enormous phone bill at the end of your trip.

If you have an Android, Blackberry or iPhone at the moment, you can make calls and text messages through the app now. The Windows Phone version of Viber doesn’t have the capability to make calls yet, although they are working on this.

Give it a go.