CNET

Samsung Electronics' Galaxy S3 surpassed the iPhone 4S as the top-selling U.S. smartphone in August, the first time that Apple's flagship phone has relinquished its position atop the smartphone food chain.

That's according to Canaccord Genuity analyst T. Michael Walkley, who checks in with retailers to see how each phone is doing.

The iPhone 4S, which initially launched with AT&T, Verizon Wireless, and Sprint Nextel, and then expanded to a number of other carriers, has held the top spot as the single best-selling phone ever since it launched in October. To have held on to that spot would have been impressive for any device, but has been par for the course for previous iPhones.

"We believe this is the first month since the iPhone 4S launched in October 2011 that it was not the top-selling smartphone in the U.S. market," Walkley said.

The weaker iPhone 4S sales likely aren't an indictment on the demand for Apple products, but merely a pause as consumers wait for the next iteration, commonly referred to as the iPhone 5. Apple is expected to unveil the phone next week, and pictures and videos have already leaked.

As a result, Apple should return to the top spot once the next iPhone launches.

While the iPhone 4S sales weakened, the Galaxy S3 numbers continue to look strong, further solidifying Samsung's position as the world's largest smartphone vendor and top Android partner.

Meanwhile, Walkley said his retail checks indicate continue weakness with Nokia, HTC, and BlackBerry maker Research In Motion. As part of the survey, Walkley checks in with 50 to 100 stores in larger cities, as well as the leading distributors. It's part of a monthly check he has done for nearly a decade.

Apple and Samsung remain locked in a number of courtroom battles over smartphone designs around the world. Apple last month won a decisive victory in a case in California, in which a jury found Samsung violated a number of Apple patents and ordered the Korean company to pay $1.05 billion in damages. On Friday, in a separate case, Apple added the Galaxy S3 and the Galaxy Note to the list of Samsung devices it says infringe its intellectual property.