I read that if you are in an app, like iPod, better to hold the home button for 4-8 seconds to be sure it closes rather than running in the background. Does holding the home button also close other apps if they are running in the background (or is it impossible for any other app to run in the background). I'm super happy with the iPhone but disappointed with the battery life. Not really a business tool (especially for business trips). Trying to save as much of the batter life (turn off 3G, WiFi and Location Services). Thanks.