Apple and Samsung have been gradually taking over the US smartphone market, Canaccord Genuity analyst T. Michael Walkley said in a research note Tuesday. Based on channel checks e saw all three iPhone models gain real-world sell-through share in November and the iPhone 4S continue to be the top seller at AT&T, Sprint, and Verizon. Samsung had achieved a rare feat, however, and saw the Galaxy S II take the second-place spot away from the regular iPhone 4 on AT&T.