Small tablet computers are marketplace hits, with economically-priced devices powered by Google's Android software taking share from Apple iPads, according to International Data Corporation.

"One in every two tablets shipped this quarter was below eight inches in screen size," said IDC research analyst Jitesh Ubrani.

"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."

International Data Corporation on Tuesday increased its tablet market forecast for this year to 190.9 million and said that it expected the figure to be closer to 350 million by the end of the year 2017.

Android-powered tablets expanded their share of the market "notably" last year and that trend is expected to continue, according to IDC.

IDC predicted that the Android share of the market would rise to 48.8 percent this year while sales of iPads would slip five percent to 46 percent.

Tablets running on Microsoft Windows software were expected to make slow gains in the market, growing from a one percent share last year to 7.4 percent in the year 2017, according to IDC.

"Microsoft's decision to push two different tablet operating systems, Windows 8 and Windows RT, has yielded poor results in the market so far," said IDC tablets research director Tom Mainelli.

"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."

The growing popularity of low-cost tablets is damaging prospects for sales of dedicated e-readers, with sales expected to grow only modestly over the next two years before going into permanent decline, according to IDC.