With viber, users can make free calls, send free texts and share location and setting.
Available for: Android/ iOS/ Blackberry/ Windows Phone/ Mac/ Nokia/ Bada/ Windows
Skype enables users to do group calls and call landlines and mobile phones at a cost.
Available for: iOS/ Android/ Windows Phone/ BlackBerry 10/ Windows/ Mac
The app offers features like Live Chat, Group chat, Video calling and push-to-talk. This app also comes with a ‘Shake’ feature to help you find new friends. To use this feature, all you have to do is shake your phone and the app will help you connect with other people, who are shaking their mobile at that time.
Available for: iOS/ Android/ Blackberry/ Symbian/ Windows Phone/ Web
This app has started offering ‘NimbuzzOut’ service, which is a low cost Pay-As-You-Go option to make calls to other mobiles and landlines numbers across the World.
Available for: Android/ iOS/ Blackberry/ Windows Phone/ Nokia/ Java
Line is another popular app that offers features similar to those in the list, including voice chat, stickers, and more.
Availanle for: iPhone/ Android/ Windows Phone/ BlackBerry / Nokia Asha/ Mac/ Windows/ Windows 8