how to whatsapp without Data

WhatApp Bluetooth is a smartphone messenger for Androids. WhatsApp Bluetooth takes advantage of your phones bluetooth to  send and receive message to/fro with friends and family without
connecting to the  internet. Use WhatsApp Bluetooth to send and receive messages, pictures messages even when your android phone doesn't have either of wifi or network connection or when you are out of data.
This app runs on android os 2.0.1 and above
and can be downloaded here.