I've updated my "old" Objective-C app to use the new storyboard with size classes, set the deployment target to iOS 8 and uploaded the new binary to the App Store. Still, the App Store doesn't show the text "this app is optimized for iPhone 6 and 6 plus". The text only mentions iPhone 5S and everything below.
What am I supposed to do in order to get the app iPhone 6 approved?
The solution was to add @3x versions for all used images and using the new size classes. You notice the app from switching to iPhone 6 supported when e.g. table cells look different (get very small) to adjust to the new screen size.
Update for clarity:
Before iPhone 6 and 6 Plus, my images were named like this:
Icon-40.png
Icon-40@2x.png
In order to get the wanted optimized for iPhone 6 and iPhone 6 Plus text, you need to add a third resolution of each image and name them with a @3x where the @2x was before. So you end up having these three images -per image you want to show in the app-.
Icon-40.png
Icon-40@2x.png
Icon-40@3x.png
IMPORTANT
You use a launch XIB or storyboard file to indicate that your app runs on iPhone 6 Plus or iPhone 6.
来源：https://stackoverflow.com/questions/26210622/optimized-for-iphone-6-info-text-in-app-store