Would you like to be able to turn on or off wifi within any application? This gives you that. You simply have to swipe down the notifications bar, and tap the icon and your wifi is turned on or off.
Have you ever found yourself sitting at home, surfing the internet, and realizing it's too slow, and you'd like to turn on wifi, but you'd have to leave the internet? No more.
Conversely, have you ever been low on battery, but don't want to go to the home screen to turn off your wifi? No more.
This gives you quick access to your wifi settings, from wherever you are.