A while back, I learned about the basic programming structures on various mobile systems like iOS, Android and webOS. Later, when I saw the news reporting rumor on some alternative resolutions we might see on the upcoming Apple iPad 2.
The truth is that iOS seems to be pretty backward in terms of how it supports on screen app layout. Unlike Andoid, which follows Java GUI tradition like Swing, has out of box layout manager APIs that supports pixel-independent laying out app UI screen details. iOS requires developers to layout screen details in pixel-by-pixel fashion in the codes. This brings us to the practicality if Apple can afford to give us a new resolution in their future iOS devices.
There is a specific reason that why iPhone 4 has a screen resolution that doubles that of previous generations on both height and width. It is much easier to support previous generation of apps, which are constructed in old resolution. You can simply do pixel doubling without doing complex screen scaling.
So, if Steve Jobs is going to eat his words and come up with a 7-in iPad, you can bet that Apple will still have to maintain the same screen resolution as the current generation of iPad since it does not want to lose backward compatibility to the apps that are specifically written for current resolution of iPad.