The Audio on Cue iPhone/iPod application allows you to create a play list using the audio items in your iPod library on your device. Unlike playing the list in your iPod application, songs are played one-at-a-time on your command - the next song in the list doesn't start until you tell it to. I created this application because I needed a better way to control the music played from my device in live events. I tried adding "silent songs" in between songs, but sometimes I still forgot or needed to attend to other things and failed to stop the player in time. This application improved the quality of my sound in my live events: no more "oops the sound guy screwed up" mistakes.
Because of the specialized nature of this application, it does not play well with others on the iPhone/iPad. If you exit the application while playing a song, the song will quit playing. When the application is not active, it may not be in control of the sound being played. Therefore, it gives up control - by design.