You'll note that each generation of smartphone tends to involve reductions in the bezel -- the hardware that surrounds the screen around the edges of the device. We're very close to being able to mass-produce phones with screens that go right to the edge.
A five-in. device with no bezel or very little bezel will bring the width of phablets down to a tolerable holding size, while still allowing for maximum screen real estate.
But wait, you might say. People use tablets like the Apple iPad with no trouble. Why would the size of a large phone be a problem?
The reason is that the size and weight of a larger tablet actually helps you hold it. When you hold a tablet with one hand, you jam the bottom corner into your palm, with your fingers holding the tablet up near the center. The weight of a tablet pulls the corner opposite from your hand down, which pushes the corner in your hand up. Your thumb and folded palm hold it down. The force of the tablet's corner pushing up substitutes for grip. The tablet's weight and size makes this kind of holding natural.
Phablet-size devices will be neither big enough nor heavy enough to be held like tablets.
People will want to hold phablets with the thumb on one edge and the fingers on the other in a proper grip, while the device rests in the up-facing palm. A 5-in. screen without bezel is just about right for this kind of holding. But with a bezel, it would be just a little too big for most people.
Meanwhile, Moore's Law and the increasing improvement and miniaturization of electronics in general will make phablets video powerhouses.
When 5-in. devices are as small as possible, come equipped with screens that have better resolution than iPhone's Retina display, and boast more powerful graphics processing, phablets will become a major, mainstream device category.
Super-high-res screens will enable users to dispense with the horrible mobile versions of websites and instead see desktop-PC-optimized versions. Games, videos and photos will look absolutely incredible. Third-party accessory makers will create keyboards, enabling business travelers to leave their laptops and tablets at home.
As the touch-tablet and e-book categories become more popular, demand will rise for larger-screen phones. We'll want better Web browsing, better image- and video-viewing, better games and better e-book reading.
In a nutshell, the era of the phablet is almost here. And it's going to be huge.
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