When you develop for iOS, you target iPhone, iPad or universal app. iPhone apps run on iPad, universal runs on both, but iPad apps only run on iPad. The apps you mention target iPad I believe.

Whilst you can retarget apps, it's not a case of just selecting a different option. There is much needed to do to fit different screen sizes. It was bad enough targeting both sizes of iPhone and the iPad even before the new sizes.

Whilst there are development techniques to ease this, I still think that there will be many a groan from developers on having a further set of sizes to support. As yet, I've not looked at how the new sizes actually appear to the developer. Retina was a cheat, and as far as the app was concerned, nothing changed screen size, and only 2x icons/images (file or programatically) were needed to make apps truly retina.

So whilst technically it's possible, effort wise it may not be worthwhile. But then, Apple have ways of forcing developers hands...

Meridian owner since 1992
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