I have had a few users tell me that on their iOS devices the AirPlay logo is gone and they could not stream to their Apple TV. A quick fix that we have found is to go to Setting>General>Reset>Reset Network Settings. After the device resets the network settings you should see the AirPlay logo is now back. You will loose all your saved wifi information if you do this just so you know. Also this might not work in all cases but I have found it works in most.