IDC (International Data Corporation).
IDC also reported that sales of handheld computers will reach 190.9 million units this year, which is more than previous speculation of 172.4 million.
Devices running Google's Android software will take over about 49 percent of the tablet market this year - again higher than IDC's prior prediction for 42 percent. IDC added that Apple's share will slip to 46 percent from late year's 51 percent.
Again, sales of smaller, cheaper alternatives to the iPad, like the Kindle Fire or Samsung Galaxy tab, are assisting Google in its advancement on Apple.
"One in every two tablets shipped this quarter was below 8 inches in screen size," Jitesh Ubrani, an analyst at IDC, said in the corporation's recent statement. "We expect smaller tablets to continue growing in 2013 and beyond." Microsoft Corp.'s Windows 8 software will be used on 7.4 percent of tablets by 2017, up from just 1 percent last year, IDC added.
As multi-functional tablets gain popularity, ones which have more solid operating systems (Microsoft Surface for example, which uses a full Windows 8 OS), fewer consumers will buy dedicated e-readers like the Kindle or Nook. That is clear to IDC, seeing as though e-readers peaked at 26.4 million units in 2011, but then slipped to 18.2 million last year. IDC expects them to "grow only modestly" this year and in 2014, before gradually declining by 2015.