The iPad has continued to gain market share even as rivals, such as the Amazon Kindle Fire, lost ground. In fact, it's the decline in the Fire's sales that has mostly contributed to the iPad's gains.

The Kindle Fire's sales slump was more severe than expected during the first quarter of 2012. During that time, the iPad controlled 68 percent of the market, a 13 percent climb from the 54.7 percent share in the fourth quarter of 2011.

The continued success of the iPad was due to its international reach, whereas the Kindle Fire was tied to the U.S. during the Christmas period. The iPad was also a hot seller during January in China, because of the country's gift-giving period.

"We expected to see a significant drop in [the] Amazon Fire [in the first quarter]. But honestly, the drop was a little bit more than we expected," Bob O'Donnell, an IDC analyst, said.

O'Donnell also said that the increase in the iPad's share shows the device remains a seasonal product, as the device's sales fell off during Q1 2012 by 3.6 million units compared to the previous three months. That's including the Chinese New Year.

"Apple's move to position the iPad as an all-purpose tablet, instead of just a content consumption device, is resonating with consumers as well as educational and commercial buyers," Tom Mainnelli, IDC's research director for mobile connected devices, added in a statement.

Both analysts agreed that positioning the iPad as something for markets such as education and enterprise sets it apart from the competition.

During April this year, Apple's CFO made a 10,000-iPad deal with the San Diego School District and he said the school planned to buy 15,000 more during the second quarter.

The IDC expects Amazon to introduce a device with a larger screen at an aggressive price point, like the Kindle Fire, while Google will re-enter the tablet market with an Asus co-branded tablet that will compete with the Fire.

Windows 8 also launches later this year, and Microsoft is set to make a push into the tablet market through the Metro UI.

(reported by Jonathan Charles, edited by Dave Clark)