Playing iOS spotify app through AppleTV

I had previously posted a quick tip about using the OS X desktop version of Spotify on an AppleTV. I've been pinged a few times by some people asking me "What about the iPhone / iPad app?"

While Spotify is playing, just double click the home button to bring up the multitasking display and swipe to the right, twice. You'll see see the airplay icon. Select the option to choose AppleTV as the audio output.