• by Mark Walsh  @markfwal, August 8, 2012

Google's Android redefined its dominance of the smartphone market in the second quarter, according to new data from technology research firm IDC. Nearly 105 million Android-based devices were shipped in the quarter, more than double the 50.8 million from a year ago.

That surge gave Android a commanding 68% share among smartphone platforms last quarter with Apple's iOS a very distant second, with a nearly 17% share on shipment of 26 million iPhones. BlackBerry and Symbian had just 4.8% and 4.4%, respectively.

Samsung in particular has helped fuel the platform's success, accounting for 44% of all Android phones shipped in the second quarter. The Taiwan-based manufacturer said in late July the flagship Galaxy S III sold more than 10 million units since being launched in June, putting it on pace to potentially sell some 40 million by year's end.

The IDC report reiterated that demand for the iPhone has cooled since the latest version came out last October and rumors abound online that the updated model could be introduced as soon as next month, leading people to delay purchases. Still, iPhone shipments increased 27.5% in the quarter.

While starting from a small base, Microsoft also saw strong gains in the second quarter, with shipments of Windows Phone devices up 115% to 5.4 million. But with only 3.5% market share in the quarter, it's still a long way behind Android and iOS. Microsoft will need strong sales of Windows Phone 8 devices launching this fall to attempt to further narrow the gap.

Separate data released by The NPD Group Wednesday highlighted the role that prepaid devices are playing in boosting smartphone adoption in the U.S. The market research firm found prepaid smartphone unit sales jumped 91% in the second quarter from a year ago, while post-paid, or contract, smartphones sales were flat.

“Prepaid smartphones are no longer just cheap, also-ran options, focused on older and less capable phones,” stated Stephen Baker, vice president of industry analysis at NPD. He added that carriers have been smart to market some of their best phones on a prepaid basis to new customers to keep sales up.

Sprint's Virgin Mobile USA in June, for example, began offering the iPhone with a prepaid plan. It meant users had to pay the unsubsidized price of $649 for the iPhone 4S, however. On the Android side, Google sells the contract-free Galaxy Nexus for $349.

NPD also noted that the income level of the average smartphone buyer is shifting downward, from middle- and upper-income families, to less affluent consumers. The proportion of smartphone buyers in the second quarter with incomes of less than $35,000 a year increased to 33% from 24% a year ago.

Apple and Samsung were the top smartphone manufacturers in the quarter, with the combined market.