Sprint unveils its first 4G phoneSource: By Kent German, CNETMarch 24, 2010 -- Updated 1414 GMT (2214 HKT)LAS VEGAS, Nevada -- To no one's surprise, Sprint kicked off CTIA 2010 here by announcing its first 4G phone.The HTC Evo 4G is not only the carrier's first WiMax cell phone--previously the carrier only has offered 4G laptop cards and the Samsung Mondi -- but also the first commercially available 4G handset with a major U.S. carrier.The Evo runs Google Android OS 2.1; finally, a new Android phone meets the world with the latest Android OS available.From the outset, the Evo is an attractive touch-screen device that closely resembles the HTC...