When my friends asked me to download WhatsApp some years ago, I had never thought that the green icon would soon be part and parcel of the smartphones of almost 450 million people. The app is quick, easy to use, and attractive and is downloadable free for everyone except iOS users. All-in-all, it is a really convenient to use fun app which does away with the woes and fluctuating rates of SMS, pervading the barriers of distance. As long as you have access to internet and a smartphone, no one can stop you from staying in touch with everyone. But have you ever wondered how this company makes money? One way that is the most obvious, of course, is the subscription fee that it charges its users. WhatsApp allows its users to enjoy the services for free for the first year after installation. However, after that it charges $0.99 for continued service. But till date, I have not heard of a single person who has paid for this extension of servi...