An analysis by London-based tech and telco analyst Benedict Evans has compiled statistics for US smartphone sales from the two largest carriers -- AT&T and Verizon -- and concluded that all new growth in the past two years from both carriers has come as a result of the iPhone. By comparison, Android sales have remained basically flat since at least 2011, with an actual drop in the most recent quarter. The analysis reinforces the notion that Android and iOS customers are entirely different groups, and should be marketed to differently.