iPad sales are forecast to drop to 46% of the market from 51% in 2012, as smaller, lower-priced Android devices gain in popularity.
At the same time, Android OS devices are expected to grow their market share to 49% – up from 42% in 2012 – with the total number of tablets sold expected to reach 190.9 million units, up from its previous forecast of 172.4 million.
However, Apple’s iPad Mini – with a screen size of 7.9 inches – could benefit from the trend towards smaller devices. Recent figures show about half of all such devices sold have screen sizes smaller than 8 inches.
"Vendors are moving quickly to compete in this space as consumers realise these small devices are often more ideal than larger tablets for their daily consumption habits,” said Jitesh Ubrani, research analyst at IDC.
IDC expects this trend to continue growing in 2013 and beyond.
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In the longer term, both iOS and Android OS are expected to give up some market share to Windows-based tablets. Windows 8 OS is predicted to grow from 1% of the market in 2012 to 7.4% in 2017.
However, IDC does not expect tablets running the Windows RT OS to grow their share to as much as 3% by 2017.
IDC said 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,” said Tom Mainelli, research director at IDC.