+ NO FEE: WhatsApp uses the Internet connection of your phone (4G / 3G / 2G / EDGE or Wi-Fi, if available) to allow you to send messages and call your friends and family; so you do not have to pay for each message or call.
+ WHATSAPP WEB: You can also send and receive WhatsApp messages in the web browser of your computer.
WhatsApp works with your phone number, just like SMS, and integrates seamlessly with your existing address book.
+ OFFLINE MESSAGES: Even if you miss your push notifications or turn off your phone, WhatsApp save your messages offline until you use WhatsApp again.