Smartphone season unofficially started last week with the release of the iPhone 4S. As Android phone makers try to capture their share of the lucrative Christmas market, the volleying for differentiators takes different angles to be as appealing as possible to consumers. For the Motorola Droid Razr, their gimmick is thickness (or lack thereof). This “impossibly thin”smartphone is equipped with a stainless-steel core, a Gorilla Glass screen and a nanotechnology Splash-guard. Motorola Mobility President Sanjay Jha said the 7.1mm-thick device is the world’s thinnest. Here are some of…