WhatsApp app allows you to exchange messages without having to pay for SMS. Better than search by Google App Store at market //details?goToHome 1 you should get Whatsapp in its official website, because link was moved, or follow links bellow:
Whatsapp free Download for Android, Blackberry, Nokia Asha, iPhone, Windows Phone, iPad and maybe in the future Fire Phone, Firefox OS, PC, Windows, Mac, Linux. Find your Whatsapp App and enjoy with your friends. WhatsApp Messenger is the number one cross-platform mobile messaging app for iPhone, BlackBerry, Android, Windows Phone and Nokia.