Q: iPhone locks up (completely) while streaming a movie using AirPlay mirroring to Apple TV and an incoming phone call is recieved.  The normal screen shows up to "slide to answer" but nothing you do on the screen works.

Specifically, I was streaming a movie from the Amazon Prime Video app using AirPlay to my AppleTV when an incoming call interrupted.  The screen on the iPhone (and the TV) changed to the normal answer a call screen, but the screen does not respond to the swipe to slide the bar and answer the call.  Neither the Home button or the Power button work either, and the phone continues to ring dozens of times after the caller has hung up.  The only way I could get out of this lockup was to do a hard shutdown by holding the Home button and the Power button down simultaneously and reboot the iPhone.  Is this a fault of the Amazon Prime Video app not releasing something, or would this same thing happen if AirPlay was streaming from an Apple app such as a Picture Slideshow?