The 3G feature in this device enables you to access wikipedia and kindle store to download books. Kindle 3G can connect to the internet via free 3G without a wireless set up. The 3G connectivity uses the same wireless network as your phone without paying any monthly fees. But your kindle may use the wireless network.
Built in Light
This is a very important feature of any kindle as it automatically adjusts the light when you are reading in a dark room or in the sunlight. This improves your e-reading experience without putting strain on your eyes.