Some day we'll be able to stretch our smartphone screens out to the size we want and make them smaller with a pinch gesture. But Kyocera came very close to that reality with the Echo phone for Sprint. It combined two 3.5-inch touch screens using a sturdy copper alloy hinge. Together, the displays gave users a whopping 960 x 800 pixels, and a handful of apps enabled users to run one one top and one on the bottom at the same time. While the 6.8-ounce weight and lack of 4G were definite drawbacks, we seemed to like this phone a lot more than shoppers did.