In terms of market share for operating systems on what researchers at IDC call smart connected devices--a definition that includes PCs, media tablets, and smartphones--Microsoft led the pack with a market share of 35.9%, at the end of 2011. Google Android held the second spot with a share of 29.4%, while Apple's iOS, which powers the iPad, iPhone, and iPod touch, was third at 14.6%.
But Microsoft will lose its top spot during the next few years as more computing is done through mobile devices, an area of weakness for Redmond but a stronghold for Google and Apple. By 2016, Android will be the number one player in the market, with a share of 31.1%, Windows will have fallen to second spot, with 25.1% of the market, and iOS will remain third, at 17.3%, IDC predicts.
"Android's growth is tied directly to the propagation of lower-priced devices," said Tom Mainelli, IDC's research director for Mobile Connected Devices.
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"While we expect dozens of hardware vendors to own some share in the Android market, many will find profitability difficult to sustain," said Mainelli. "Similarly, we expect a large percentage of application developers to continue to focus their efforts on iOS, despite the platform's smaller overall market share, because iOS end users have proven more willing to pay for high-quality apps."
IDC expects the overall market for smart connected devices to grow from 916 million units shipped in 2011 to 1.84 billion units in 2016. "In many if not all instances, the smartphone will be the primary connection to the Internet," said Will Stofega, IDC's program director for Mobile Phone Technologies and Trends.
As more computing goes mobile, Microsoft is getting left behind. The company has had only limited success with its Windows Phone 7 platform, despite an alliance with handset maker Nokia, which is costing Microsoft billions of dollars in transfer fees.
Microsoft's share of the U.S. mobile market was just 4.4% as of January, compared to 29.5% for Apple and 48.6% for Google, according to the latest data from Comscore.