What happened to iPhone 5 will happen to iPad 5 & iPad mini 2. There screen size will grow from 2048 x 1136 to 2280 x 1136.
When I was working on my App Wallax (still in review), which generates Wallpapers for iPad & iPhone, I noticed something peculiar. When I set a wallpaper on iPad, it did not fit the screen. It was slightly movable by 160 points. No such thing happened in iPhone, the wallpaper was fitting the screen.
While rumours of October 22 iPad 5 and iPad Mini 2 event is around, I believe that the developers have left a clue in iOS 7 about the iPad 5 & iPad Mini 2's new increased screen size.
I think the thing that happened to iPhone 5 is going to happen to iPad 5. For the first time iPad screen size is going to change.
One more reason that makes me to strongly believe this is that iPhone 4 is becoming deprecated. With iOS 8 it will be completely out. Currently the developers have to support both iPhone 5 & iPhone 4 screen sizes. Going forward they will have to develop only for iPhone 5 screen size and next versions.
The apps developed only for iPhone still runs on iPad. iOS 7 uses the Retina assets of the iPhone-only apps to improve the 2x mode even on non-Retina devices. Interestingly, Apple doesnt even provide the 1x/2x toggle on non-Retina devices such as the iPad mini and iPad 2. This shows that Apple has given some serious thought to usability of iPhone only apps on iPad.
Currently only the iPhone 4 version is displayed in the iPad, main reason is that only iPhone 4 screen version (small screen 640 x 960) fits into the iPad screen size (768 x 1024). If iPhone 4 becomes deprecated, developers will only develop for iPhone 5 screen size(1136 x 640). There will not be a iPhone 4 version to display on iPad and also iPhone 5 version will not fit into iPad. Its high time for Apple to increase the iPad screen size from 1024 x 768 to more than 1136 x 768. I believe that change is coming with iPad 5 & iPad Mini 2.