Apple does not impose any resolution requirements for Mac. I don't see anything in IB that forces that for iOS either. All the same autosizing and non pixel based coordinate systems are there.
Have you ever made Cocoa software before ?
First, it's not a bitmap based OS. OSes don't have any kind of graphics requirement. iOS devices use a bitmap display. But so does Windows. So does X11. So does Quartz on OS X. The end result is a bunch of pixels aligned on a grid.
So you don't really have a point there, you're only repeating the same thing everyone is. The fact is, bitmap displays have been around for much longer than iOS and have never had a fixed size. Yet developers have managed to write software for all these other platforms that use these bitmap displays for ages without ever knowing the final resolution at which their app would be displayed. And it all just worked.
You don't have to even know what the future holds in order to write proper code that doesn't assume the end resolution. This is a problem that was solved ages ago in computer science.
Is it really that hard to grasp ?
Apple is quite specific on pixel sizes. Here, read for yourself. Pretty easy to find.
http://developer.apple.com/library/...eptual/mobilehig/IconsImages/IconsImages.html
It is a bitmap OS. Pull the entire OS and look at the files yourself. The interface is just a bunch of PNG files. For example, the animation of the trash can when you delete a picture is really five PNG files of a trash can in various states of opening and closing. Thats it. If you did this, you would see most of the graphic elements in the OS are just PNG files. If you don't believe me, do it yourself.
If this is news to you, I don't know what else to say.
As to it being an issue with OS's - yes it is. How others OS's deal with it is to keep the pixel size of the bitmap elements, thereby making them appear bigger or smaller on the screen depending on the DPI of the screen. This is why the titlebar of a MacBook looks bigger then that of a 17 MacBook Pro. They are both the same number of pixels, but since the 17 MacBook has a higher DPI screen, it looks smaller. Follow me so far? Good. So we agree that other OS's deal many times with different resolutions by keeping the bitmap elements the same pixel size on the screen. Very good.
Now what would happen if current iPad apps did this this on a higher res screen that is not 264 DPI ? Yep, you get a picture frame effect, where the app is surrounded by large black bars. So sure, it could behave like other OS's as you suggest, but is this a good user experience ? No. If it went the 264 DPI route, it could just double up and make for a much better user experience w/o fragmentation.
Alternatively it can scale up apps using interpolation, but as we all know, that can get ugly.