As far as I know, some apps quit by pressing the Back button while on the main screen of that app; and some quit by pressing the Menu button and selecting Quit. Should I always first check the Menu button? How can I make sure that I have quit a specific application? I don't want my battery drained by unquit apps running in the background without my knowledge.
By the way, I'm on HTC HD2 with Android 2.2.