Think you know what the most popular smartphone is? It actually depends on how you ask the question.

In a new report from technology research firm IDC, Android models now account for 75 percent of the global smartphone market, with Apple's iOS coming second with 15 percent. The report looked at third quarter shipments of devices. As an individual brand of device, Apple's iPhone is still on top, but is being seriously challenged for the first time by the Samsung Galaxy.

If this seems conflicting, it's not because it's a matter of brand versus operating system. Only one brand of smartphone runs on Apple's iOS, the iPhone, of course, but there are dozens of companies that produce smartphones that run on Google's Android platform.

The issue is similar with the market for laptops and workstation computers, where Apple is one of the top individual brands, but computers running on Windows account for more than 82 percent of the market.

In IDC's report, only the Android and Apple mobile operating systems were in double digits. Android, which is developed by Google, saw an increase of 7 percent over the same period last year. Apple's iOS was up 1 percent from last year. Their gains came mostly at the expense of BlackBerry, which saw its share decrease by 5 percent, and Symbian, which dropped by 10 percent. Symbian was, until recently, the mobile OS on most Nokia devices. That company is shifting to the Windows platform.

The Windows mobile platform came in with a 2 percent share, but it is expected to rise in the fourth quarter with the recent release of the latest version. Likewise, some analysts believe BlackBerry may see some resurgence early next year when the developer, Research in Motion, releases a new OS and new smartphone models. Linux came in at 1.5 percent.

The original smartphone is usually cited as Palm's Kyocera 6035, which debuted in 2001 and ran on the Palm OS. It was the first to combine many of the features of Palm's popular late 1990s line of PDAs with a cell phone.

The IDC report reflected worldwide shipment of more than 181 million smartphones in the third quarter of 2012, an overall increase of nearly 50 percent over last year.