I like everything about this app.It is simple in everything and very useful in not only chatting but also in some daily works.Whatsapp is an American company owned by Facebook.The concept of the app is simple that is to provide the user free unlimited chatting experience not only text but now voice and video too.Earlier it was only text but as time passes it also provided voice and video chatting facilities.The layout and design is also simple that is why it is becoming very popular among non-tech people too.Features are good.As I mentioned earlier it is very useful in day to day life too.Its end to end encryption facility is the best.I would suggest people to use it once.