Google’s Android operating system accounted for 52.5 percent of all smartphones sold in the third quarter of 2011, according to market research firm Gartner, more than doubling its market share from the same period in 2010.

Gartner made the data available in a press release on its website, along with a lot of other numbers about the worldwide mobile device market. It found that smartphone sales leapt up 42 percent in the quarter that ended on Sept. 30, compared to the same time last year.

Gartner’s data finds that 115 million smartphones were sold during the third quarter of 2011 around the world. Smartphones accounted for 26 percent of all mobile phone sales worldwide, increasing just 1 percentage point over the same period last year. Meanwhile, sales of mobile devices all types around the world increased by 5.6 percent in the third quarter of 2011 as compared to 2010, with 440.5 million units being sold around the world.

As compared to the second quarter of 2011, however, smartphone sales actually declined by 7 percent. Like other sources, such as Apple, Gartner blamed people waiting for new smartphones for the decline. When it released its financials for the quarter that ended Sept. 30, Apple reported it sold roughly 30 million fewer iPhones than it had during the same period in 2010. Its answer for the drop was the run-up to the release of the iPhone 4S in October. With customers waiting for the new device, they stopped buying older iPhones.

Gartner suggests it might not have just been Apple that felt this effect, with Android device owners waiting for new flagship phones to hit during the last quarter as well. Smartphone volume continued to increase thanks to emerging markets, including China and Russia, but the desire for cutting-edge devices on the horizon slowed sales in the U.S. and Western Europe, the research firm says.

As was noted after Samsung released its financial report for the quarter, the South Korean device manufacturer has become the No. 1 smartphone manufacturer worldwide, racking up 24 million sales and tripling its numbers from the same time in 2010. But Gartner expects strong competition from Apple in the next quarter with its iPhone 4S, which is already reportedly breaking sales records.

Meanwhile, Nokia continues to be the leading manufacturer of mobile devices in general worldwide. It grabbed 23.9 percent of global mobile device sales, rebounding slightly from the second quarter of 2011, but that was mostly on the back of the company’s feature phones, rather than smartphone sales. Nokia continues to lose market share to Apple and Google this year, and Gartner doesn’t expect the Nokia to really turn things around until midway through 2012.

Gartner’s numbers show some big growth for Android during the last quarter, and it seems like the operating system will continue to gain ground with the increase of more and more great smartphones from various manufacturers. Meanwhile, Apple should continue to be a force to be reckoned with in the next quarter, if the iPhone 4S is any indication. But even with record-breaking sales, it looks like Android will likely continue to gain ground just on the sheer volume of devices it offers, as it has in the past.