The free Vonage Mobile application for Facebook lets you call your Facebook friends anywhere in the world if they have the same app downloaded in their iPhone or Android.
It is available for Android phones in 48 countries and in 87 countries for iPhone or iPod Touch and is available from Vonage Facebook fan page. You can also invite your friends to download the mobile application.
After downloading this app, you enter your Facebook ID and password for the first time.
The software then automatically loads your Facebook contacts and separates them into two groups. One with friends who downloaded Vonage mobile app and you can call them for free. Other group shows Facebook friends who are available for instant messaging.
Just, touch the friend’s name from the Call Free list and your free call is connected.