Originally Posted by dturner
I may still not understand the question. The pause button is the same as "stop". You don't need to do anything further to "shut off" the ipod function.

I believe I understand what
MNJON is referring to. Consider how Windows Media Player works on the Windows platform as a point of comparision. Windows Media Player is either running or not, can be completely shut down (no process consuming memory), and while running can be in one of three states: no media file selected, selected media file playing, or selected media file paused.
In contrast, once the IPhone's IPod application is "started", it appars as if it is either running in the foreground or the background. Additionally, once the application is "started" it seems to only allow for two states: last selected media file playing or last selected media file paused.
Once you start playing a song in the IPod application, a "Now Playing" indicator appears at the top of the various screens. Leaving the IPod application and returning continues to show the "Now Playing" indicator. This gives the sense that you've simply put the song on pause and put the IPod application in the background. Obviously, with the battery life such that it is, the idea of an application running in the background when you aren't using it is troublesome.
The real question is whether the IPod application is actually in a different state between when you first start up the IPhone and when you have a song on pause and are not in the IPod application. When a song is on pause and you've exited back to the main IPhone screen, is the IPod application still running? Is it ever not running and the difference is whether is tracking the last selected song?