Apple already does and the media companies already do. At least, when it comes to AirPlay Mirroring: https://developer.apple.com/library/safari/#documentation

Apple already does and the media companies already do. At least, when it comes to AirPlay Mirroring: https://developer.apple.com/library/safari/#documentation/AudioVideo/Conceptual/AirPlayGuide/EnrichYourAppforAirPlay/EnrichYourAppforAirPlay.html#//apple_ref/doc/uid/TP40011045-CH6-DontLinkElementID_7 https://developer.apple.com/library/safari/#documentation/Au... Basically, you can subscribe to a notification when a second screen is connected and display there whatever you want. The French TV channels M6 and Canal+ have blocked it for a few months now. (which is absolutely stupid obviously) As far as AirPlay from inside the default media player object, I'm not sure if it's notified to the app and I don't have an iPhone 4S or iPad2+ to check. edit: the paragraphe "Provide Audio Metadata" from the link above seems to say that the app also knows when it's "plain" AirPlay.