Both Enderle and IDC's Mainelli said large smartphones, meaning those that have displays of six inches or more, will potentially cannibalize tablets with smaller displays of seven inches or so.
"The iPod Touch has pretty much been eliminated by the iPhone, and I think the iPad mini is likely to be eliminated by the iPhone, while the iPad and the MacBook Air are likely to become redundant to each other," Enderle added.
Other emerging technologies, such as 3D gesture controls, voice controls and projection technology, could eliminate the need for physical keyboards or displays, and could place greater reliance on a smartphone or a similar device as a wireless processing hub in a workspace.
"Tablets will sell well for a few years, but with things like Google Glass and projection technology, which projects a screen on any surface, the concept of a tablet is less relevant," said J. Schwan, the CEO of Solstice Mobile, an enterprise mobility consultancy that works with companies like Sprint and industrial parts supplier W.W. Grainger to implement ubiquitous mobility systems.
Schwan said Heins' comments provoked spirited debate among designers and engineers in his Chicago office over the future of personal computing.
"A lot of our current work is getting people off of laptops and moving towards 100% use of the handheld device," Schwan said in an interview. Solstice is testing Google Glass, Nuance's voice navigation and Leap Motion's 3D sensor technology. Leap Motion's controller senses a user's hands and fingers in order to follow every move as precisely as 1 centimeter by 1 centimeter. The technology could be precise enough to detect finger movements similar to striking an actual keyboard, Schwan said.
With that kind of vision, where users are interacting in 3D, "the screen becomes less of a constraint, so you just need a device with wireless connectivity that can process data," Schwan said. "Screen size is less of an issue. It could be that's where Heins is going" with BlackBerry.
This article, Blackberry CEO's comments ignite debate on future of personal computing, was originally published at Computerworld.com.
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