It's not rocket science. Apple's continuously working on next-generation iPad prototypes. Given the realities of time, technology, and economics, they're seeing how far they can go and how quickly. Some are more conservative, bringing faster, more efficient processors, better radios, and other components to existing chassises. Others are more radical, bringing new technologies, materials, and designs to market. Some are quiet ticks that need to be used to be appreciated. Others a noisy tocks that need only be seen to be believed. The iPad 4 was very conservative. The slightest tick. A new Apple A6X processor, a new, more internationally-friendly LTE radio and more robust Wi-Fi, new cameras, and the new Lightning connector. It built on the Retina display of the iPad 3, and continued once again the same chassis as the iPad 2, the last big design tock.
But now Apple has a new design language for their mobile devices, and a new way of manufacturing them that borders on machinist porn. It's what let them make the iPhone 5, and it's what let them make the exquisite, and very similar looking iPad mini, iPod touch 5, and iPod nano. It's what made for unified, ultra-thin, ultra-light, ultra-high precision, anodized aluminum unibodies with tighter curves, smaller bezels, and pixels so close to the surface it's like you're really touching them. It's what made the just-released iPad 4 look and feel old and dated by comparison.
It's not rocket science to think the iPad 5 might bring Apple's larger tablet into that new design language and manufacturing process.
There are challenges that need to be overcome, however. A 2048x1536 Retina display requires a lot of light and a lot of power. That's why the iPad 4 is so thick and heavy compared to the non-Retina iPad mini. For that device, Apple sacrificed pixel density for lightness and battery life. With the iPad 5, there's no pixel density to sacrifice. The screen is set. There's only better LED and panel technology, more efficient chipsets, and better battery chemistry to overcome it.
If Apple can get all of that in place, if they can produce an iPad 5 with Retina display, 10-hours of battery life, and make it anywhere close to as light and thin for its 9.7-inch size as the iPad mini is at 7.9, then it's hard to believe they wouldn't do it, and unify the design language and manufacturing processes of their mobile devices.
The rough concept image above shows just that -- the iPad mini design applied to a 9.7-inch screen. The current iPad 4 outline is left in the background to highlight that, in addition to being lighter and thinner, the iPad mini design on the full-sized iPad would presumably be smaller as well. Same power, far less packaging.
For those who switched from the Retina iPad to the iPad mini, who gave up pixels and power for portability, it would make the lines blur. (As would a Retina iPad mini, when that device launches.)
It still wouldn't be something you could grip in one hand like the iPad mini. The multitouch technology that lets the iPad mini reject unintentional input from the thin bezels would likely be even more critical, given how a full-sized iPad is held and used. And no matter how thin and light an iPad 5 is compared to an iPad 4, it still wouldn't be as thin and light as an iPad mini, and it wouldn't fit in as many pockets or purses.
So the question becomes, if Apple could make the iPad 5 look and feel like an iPad mini, would that be your next iPad?