The numbers come from a survey by Gartner, looking at the third quarter of 2011, and comparing it to the same quarter a year ago. Overall, it found that smartphone sales worldwide were up 42% compared to a year ago, which makes the Windows Phone sales decline particularly alarming for Microsoft. Windows Phone sales dropped from 2.2 million a year ago to 1.7 million this quarter. Its market share declined from 2.7% to 1.5%. Android, meanwhile, had 60.5 million in sales for the quarter, up from 20.5 million a year ago. Its market share leaped from 25.3% to 52.5%. The iPhone sold 17.3 million in the quarter, versus 13.5 million a year ago. Its market share was 15%, down from 16.6% a year ago.
As for Nokia, the news was bad as well. It sold 105.4 million phones in the quarter compared to 117.5 million a year previous.
These numbers show just how much Microsoft has riding on new Nokia phones. Just yesterday, a joint Appcelerator/IDC survey found that 38% of developers are "very interested" in developing for Windows Phone 7, a leap of 8% compared to the last quarter. That interest was in large part because of the Nokia deal and because of the quality of Nokia's Lumia 800 Windows Phone 7 device.
Generally, where developers go, consumers follow. But given these new numbers that show how badly Windows Phone is doing, that may not eventually be the case here.
Note: The first version of this blog referred to sales of Windows Phone 7 devices, rather than sales of Windows Phone (and Windows Mobile) devices.