WhatsApp

Whatsapp is a social app which was created in year 2009. 
It was founded by Brian Acton and Jan Koum.
Both were employees of Yahoo.They left yahoo in 2007 and started working to create whatsapp and finally created in year 2009.

They also applied for facebook but got rejected.
At starting ,whatsapp got a lot of issues.They were very disapointed and wanted to end this project but later they decided to continue for some more time.This project was not possible without an iphone developer.

It’s first version included the function of texting only.
At one time ,it’s users became so much that it was becoming difficult to handle the traffic.So they decided to charge users for it.
But this does not worked as it decreased the number of users.

Afterwards,whatsapp introduced it’s new feature in which one can transfer photos and files etc.
Third version of whatsapp included a new feature which was the call option.One can now easily call his/her friends using whatsapp.
It is a great social app which is used nowadays in almost every country with a large number of users.

It is available for all systems which include these four systems.

1.Android
2.Iphone
3.Windows Phone
4.Blackberry

It was first of all available for iphone,later it was available for android and blackberry.After that it was made available for 
Windows Phone. Now everyone can enjoy whatsapp in their device.