Android devices made up a 34 percent share of phones shipped in the U.S. market in the quarter, followed by Research In Motion at 32.1 percent and Apple with 21.7 percent, Canalys found.
That means Android had a huge 851 percent growth rate over the previous year in the U.S. That's largely because a year earlier there were few models of Android phones available.
Canalys also said that the U.S. is the largest smartphone market in the world by a big margin, with 14.7 million phones shipped in the quarter, accounting for 23 percent of global shipments.
Nokia continues to maintain the lead on a worldwide basis, with 38 percent market share in the quarter. It accounted for 76.9 percent of smartphones in China, the second largest smartphone market in the world, followed by Motorola with a 4.7 percent share there, Canalys said.
Still, the researchers see a potential for Android growth there too. Nearly 475,000 Android phones were sold in China in the second quarter, up from almost none last year, Canalys said. Also, China Mobile continues to develop its own platform based on Android and sold an additional 174,000 phones in the quarter based on that platform, Canalys said.
Overall, the smartphone market grew by 64 percent worldwide in the quarter. RIM phones grew by 41 percent and Apple's iPhone shipments grew 61 percent. Apple had a worldwide smartphone market share of 13 percent during the period, Canalys found.