I'm not sure computing is going to have a major revolution, unless we see a massive AI breakthrough. The reason is that the amount of computing power available for a few watts and tens of dollars today now vastly exceeds any idea of what to do with it. With all the data in the cloud stuff the limitations are storage related (i.e. just the time to read data off disk), and the use of the CPUs is really fairly low compared to how long they sit around waiting.
Post iPhone is the best example, because all that's really happened is a (much needed) improvement in the underlying networks and a shake up of the business side of the ecosystem, but very little of this stuff that is actually used wasn't available before. There was a gold rush, but I think history is going to judge that era quite harshly in terms of lack of real progress.
Arguably, even in '99, the idea itself was old - those of us working on stuff like that then, were looking back at Star Trek and other SF, and it was just the feeling that it was an idea whose time had finally come.
Apple's genius with the iPhone and iPad, was realising its time had not come, and waiting and refining their design until the basic underlying hardware "caught up" and they could provide a product suitable for "normal users". Everyone else got to make the expensive mistakes; most of the companies involved are no longer around, or pulled out of that market before Apple made its entry.
Sometimes ideas are just not right yet, and spending time trying to force the issue is likely to fail because the end result will be massively compromised.
But sometimes the ideas are just not right yet also because the public has not "caught up". It's not just that software developers must figure this out, but end users must have caught up enough that the new ideas fit into their world view.
Aren't you forgetting that Apple made the Newton?
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Only real example that comes to my mind is PA kind of applications of the type of Google Now/Siri. But still they don't work to the level we desire them to