Originally Posted by Shaun, UK
The only difference between an iPod Touch and an iPad is that some apps look better on a larger screen.
Come on, man, you're smarter than that!
You really can't see how the HW in the iPod Touch is different than in the iPad?
You really can't see how the UI in the iPod Touch is different than in the iPad?
You can't see that one has a 3:2 display and the other 4:3 display? I use this example because it affects both the HW and UI. I've detailed how the icons don't even use the same number of pixels.
Here is another one that directly shows that scaling the OS without considering the user experience is not
The iPad icons are larger in both size and pixels and have more space between them. I'd say the icons would be too small if everything was simply adjusted down without concern for usability as we've seen with vendors using Android. They might even be smaller than on the iPhone but with more space between them (I'll have to run the numbers). This means that they would need to adjust the spacing to idealize the contents for the primary I/O and form factor.
iPhone app icons are 57x57 px and 114x114 px. iPad apps icons are 72x72 px. That means iPhone icons are 0.34"x0.34" and iPad icons are 0.55"x0.55" in size. To shrink the iPad down to 7" with the 1024x768 display you get 0.39"x0.39" icons. That's actually doable being that close to the iPhone icon sizes yet being 4x the display area and having all that extra space between icons is not how Apple would release a UI. It will be idealized or I'll short the company.
Taking the 960x640 resolution of the iPod Touch and making that 7" reduces the PPI back to what it was on the original iPod at 480x320 which really isn't a bad thing in a tablet because you do hold it farther from your face, especially when you consider that such a move would be to capture the lower-end of the market. It would be 165 PPI which would make the icons 0.44"x0.44" which is right between what they are on the iPod Touch and iPad. That actually make this sounds reasonable as many aspects of the UI would fall in-line unlike doing a shrink of the iPad UI making it easier for Apple and devs. BTW, the Kindle Fire and Nook Color displays are 169 PPI.
So if the only difference between the iPod Touch and the iPad is that "some" apps look different then why do we have so much effort taken just with the number of pixels and spacing of icons used on these otherwise exactly the same
devices? The only rational answer is that these devices are not identical, not made to be identical, and that a lot of effort was taken to idealize the HW and SW to maximize the user experience.