Before you start reading this chapter, I want to share something with you; as I was writing this chapter, my wife Anamika, was taking a selfie and uploading it to several social media sites such as Facebook and WhatsApp. She keeps a track of the likes, However, uploading more photos uses more mobile data, and mobile data costs money. I rarely use social media as I prefer to avoid paying more to the internet company. Every month, the internet company knows how much to bill us. Now consider what would happen if the internet usage, total call duration and bill calculation was meticulously planned and managed by us? It's possible that some obsessive internet users would manage it and I'm really clueless as to how.

Calculating billing for internet usage and calls is an important function, but it is still...