What is all about this whats app?

[Mbalire]

i hear people talking about this whats app ,i want to know wats all about it,how to join it and wat requires and may be its impontance

[shaunak]

you just need to give your mobile no,country you are done
its like a chat where you can create groups
example class 12,the mad guys ;whatever you can select the admin
(now whatever is displayed can only be viewed/displayed by whom admin accepts)
post pics/videos/chats
provided you know their no. and they accept
(like adding friends in facebook)
without the facebook problem of ads