Improving Windows 8 is Microsoft's best bet for grabbing a larger share of tablet sales over the next four years, but there doesn't seem much it can do to accelerate the projected slow growth of Windows RT over the same time period, IDC says.
"Microsoft's decision to push two different tablet operating systems, Windows 8 and Windows RT, has yielded poor results in the market so far," says Tom Mainelli, IDC's research director for tablets. "Consumers aren't buying Windows RT's value proposition, and long term we think Microsoft and its partners would be better served by focusing their attention on improving Windows 8. Such a focus could drive better share growth in the tablet category down the road."
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Windows 8 runs on x86-based machines and Windows RT runs on ARM chips bundled with locked-down hardware.
IDC's revised projection is good news for 2013 Android tablet sales which have been revised upward from 41.5% last year. Apple is paying the price, slipping from 51% in 2012.
By the end of 2017 Windows tablet share will increase to 7.4%, chipping away at both Android and iOS tablets, which will command 46% and 43.5%, respectively.
IDC has boosted its projection about the number of tablets that will ship this year from 172.4 million to 190.9 million, a 10.7% jump. This is based on increased popularity of low-priced devices, half of which have a screen size smaller than 8 inches, according to IDC's Worldwide Quarterly Tablet Tracker. Shipments of tablets in 2017 will be more than 350 million, IDC says.
Those smaller tablets will continue to grow in popularity, says Jitesh Ubrani, a research analyst for IDC's tablet tracker. "Vendors are moving quickly to compete in this space as consumers realize that these small devices are often more ideal than larger tablets for their daily consumption habits," he says.
The growing popularity of small tablets will undercut sales of dedicated e-readers, which will decline permanently starting in 2015, IDC says.