The nerdy past-time of comparing Android and iOS device sales figures is once again at the front of minds, as Nielsen today posted some interesting U.S. smartphone sales figures for the past three months ending in May. After undergoing a tremendous growth spurt, sales of Android devices have flattened out at 27%. Sales of Apple’s iOS devices have managed to regain some momentum, jumping from 10% in February to 17% in May, while RIM’s BlackBerry continued its downward spiral going from 11% to 6% over the same time period. In terms of overall smartphone market share, Android is still the leader in the U.S with 38%, followed by Apple’s iOS at 27%, RIM’s BlackBerry at 21%, and the defunct Windows Mobile at 9%. Wondering where Microsoft’s Windows Phone 7 stands? A paltry 1%. Yikes.

[Via Nielsen]