A new report from research firm Gartner reveals that the top two platforms in the mobile market remain Android and iOS, which have now doubled to a combined market share of 62 percent. The report is based on worldwide sales figures for mobile devices to end-users for the second quarter of 2011. That total has reached 428.7 million units, a 16.5 percent increase from the same quarter last year.

Looking at worldwide mobile device sales to end-users by vendor, it appears that Nokia is in the lead, at least based on volume. However, this is only temporary notes Roberta Cozza, principal research analyst Gartner. The bump in volume was largely due to retailers trying to jettison Symbian inventory by cutting prices. And now that Nokia’s channels are quite lean, next quarter’s results should show a major drop for Nokia.

Samsung saw incredible growth thanks largely to the success of the Galaxy S II smartphone, which has seen 5 million units in sales by the end of July. However, the company’s lack of lower-end offerings have held it back. Apple, on the other hand, continued to exceed expectations even though the iPhone 4 model is near replacement thanks to Apple’s expansion into 15 new countries and the addition of 42 new carriers worldwide.

Research In Motion’s share has declined by 12 percent, which furthers its downward trend of 19 percent the year before. It also lost its fifth place position to ZTE. It still has to face increasing competition for its enterprise space as well as deal with a major transition from its BlackBerry platform to QNX.

When it comes to mobile operating systems, Google’s Android reigns supreme with a 43.4 market share in the second quarter of 2011. Symbian comes in second due to the reasons we specified earlier, while iOS comes in third.

[via Gartner]