Whatsapp is a powerful cross-platform messaging application that allows you to exchange messages within and across networks irrespective of your location without paying for it.
Whatsapp has revolutionized instant messaging concept. It has the ability to enable users share images, videos and even allow free calls within the application network.
This suggest that you can make free calls from your whatsapp application to another user of whatsapp on another number with paying for it.
One great phenomenal features of this software is the Whatsapp Group. This facility allows users to chat in a group.