I have iPhone 5 and iPad mini updated to iOS7, and a new generation Airport Express and a 3rd gen Apple TV.
I can no longer use my Apple Remote app to control the Apple TV, it never recognises it.
I also can't AirPlay from either device to my Airport Express. I have a MacBook Pro and that AirPlays without issue.
It used to work! Apparently I can AirPlay from my iPhone and iPad to the Apple TV however...
I also have an iPad 1 running iOS 5.1.1, and this also does not see the AirPort Express.
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