Total worldwide tablet sales are forecast to reach 118.9 million units this year, with Apple accounting for 73 million of those. Total sales will grow 98 percent from 2011, based on Gartner's projections.
The research firm sees Apple's iOS maintaining its position as the dominant tablet operating system. Apple's projected share would be good for 61.4 percent of tablet sales to end users this year.
Gartner sees Apple maintaining its leadership position even as competitors such as Microsoft's Windows 8 come to the market later in the year.
"Despite PC vendors and phone manufacturers wanting a piece of the pie and launching themselves into the media tablet market, so far, we have seen very limited success outside of Apple with its iPad," said Carolina Milanesi, research vice president at Gartner.
"As vendors struggled to compete on price and differentiate enough on either the hardware or ecosystem, inventories were built and only 60 million units actually reached the hands of consumers across the world. The situation has not improved in early 2012, when the arrival of the new iPad has reset the benchmark for the product to beat."
Finishing second to iOS this year, based on Gartner's predictions, will be Android, which the firm believes will be installed on 37.9 million tablets sold. In a distant third is Microsoft, which is forecast to sell 4.9 million tablets this year.
"It appears that this year competitors have waited to see what Apple would bring out â because there were very few announcements of new media tablets at either the Consumer Electronics Show or Mobile World Congress," Milanesi said. "Many vendors will wait for Windows 8 to be ready and will try to enter the market with a dual-platform approach, hoping that the Microsoft brand could help them in both the enterprise and consumer markets."
By 2016, Gartner believes Apple will sell 170 million tablets in a single year, continuing to lead Android at 138 million. Microsoft is seeing accounting for 43.6 million tablets in 2016.
"IT departments will see Windows 8 as the opportunity to deploy tablets on an OS that is familiar to them and with devices offered by many enterprise-class suppliers," Milanesi said. "This means that we see Windows 8 as a strong IT-supplied offering more so than an OS with a strong consumer appeal."