How is 520 different from 720?

I was looking at hardware configuration of nokia 520 and 720, they look similar to me. I mean they have 512 MB of RAM and same processing capabilities! I didn't check about camera, as I don't care about it when I play games :D

So, can anyone help me in understanding the difference between 520 and 720? :)

Basically the 720 gives you a slightly bigger screen, NFC, a front camera, better main camera, and bigger battery. There isn't a huge difference between the two.