Hey,
I just downloaded WhatsApp Messenger on my Android.
It is a smartphone messenger which replaces SMS. With WhatsApp, you'll get fast, simple, secure messaging and calling, available on phones all over the world.
WhatsApp is available for Android, iPhone, and Windows Phone, and uses your phone's Internet connection to send messages so you can avoid SMS fees.
Get it now from https://www.whatsapp.com/download/.