Tablet shipments are expected to overtake total PC shipments by 2015 as low cost devices flood the market, according to research by IDC.
The shift will be seen as early as the fourth quarter of 2013, but PC shipments will still remain higher for the year, while smartphones account for 69 percent of all smart devices shipped.
Cheap tablets and smartphones costing below $350 will make up $423.1 billion of the $622.4 billion smart device value in 2013.
"At a time when the smartphone and tablet markets are showing early signs of saturation, the emergence of lower-priced devices will be a game-changer," said Megha Saini, Research Analyst with IDC.
"Introducing new handsets and tablet devices at cheaper price points along with special initiatives like trade-in programs from Apple and BestBuy will accelerate the upgrade cycle and expand the total addressable market overnight."
The PC, smartphone and tablet market is set to grow 27.8 percent this year.
But tablets face stiff competition from so called 'phablets' – smartphones with a screen over five inches.
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"The device world has seen several iterations of cannibalization impacting different categories, with the last few years focused on tablets cannibalizing PC sales," said Bob O'Donnell, program vice president of Clients and Displays at IDC.
"Over the next 12-18 months, however, we believe the larger smartphones, commonly called 'phablets', will start to eat into the smaller-size tablet market, contributing to a slower growth rate for tablets."
The decline in PC shipments is expected to continue. By 2017, total PCs are expected to drop to 13 percent from their current level of around 20 percent, while tablets and smartphones will contribute 16.5 percent and 70.5 percent respectively to the overall market.
—By CNBC's Arjun Kharpal: Follow him on Twitter @ArjunKharpal