Bill Gates has argued that users are frustrated with the iPad because the Apple tablet lacks some of the functionality found in traditional PCs.
In the second half a CNBC interview alongside Warren Buffett (below), Gates was asked about reports that tablets would overtake PCs as well as the growth of the cloud. Gates argued that Windows 8 "is revolutionary in that it takes the benefits of the tablet and benefits of the PC" and supports both.
Those who purchase a Surface Pro or Surface RT, for example, have the "portability of the tablet, but the richness in terms of the keyboard [and] Microsoft Office," Gates said.
Going forward, it's going to be "harder and harder to distinguish" between PCs and tablets as hardware manufacturers embrace form factors like convertible laptops or detachable keyboards like Microsoft offers for the Surface, Gates said.
"With Windows 8, Microsoft is trying to gain share in what has been dominated by the iPad-type device," he continued. "But a lot of those users are frustrated; they can't type, they can't create documents, they don't have Office there."
There have long been rumours about Office for iOS, but thus far, neither Microsoft nor Apple have made any announcements.
With Windows 8 and gadgets like the Surface, Microsoft is providing users "with the benefits they've seen that have made [PCs] a big category, but without giving up what they expect in a PC," Gates said.
That philosophy, however, has not yet translated into sales. According to recent stats from IDC, Microsoft shipped 900,000 Surface tablets during the first quarter, whereas Apple shipped 19.5 million iPads.
Of those 900,000, IDC said that many were the more full-featured Surface Pro, which started shipping in February in the US, before Microsoft started expanding availability around the globe last month.
Meanwhile, Gates was also quizzed on Apple's fluctuating stock price. The former Microsoft chief defended Cupertino somewhat by arguing that "whoever's the leader is always questioned."
"[Critics] always say, is this the end of them? And there's more times that people think that's the case than it really is the case," Gates said.
Apple, Google, and Microsoft are "amazingly strong companies," Gates said, with firms like Amazon, Facebook, and Samsung nipping at their heels. "The software business is an amazing business to be in, both in terms of growth and the profitability dynamics," Gates concluded.
Gates's comments come shortly after BlackBerry chief Thorsten Heins told Bloomberg at the Milken Institute conference that within five years, "I don't think there'll be a reason to have a tablet anymore."
Buffett, meanwhile, joined Twitter earlier this week, announcing his arrival on the micro-blogging site with a quick message: "Warren is in the house." He later tweeted a link to an essay that discussed "on why women are key to America's prosperity." You can follow the billionaire via @WarrenBuffett.