Originally Posted by
littlewaywelt
if it only works in the foreground does that mean you have to keep touching the screen to keep it from going to sleep? does it continue to work if you hit the power/sleep button without closing the app by hitting the home button?
You can keep it from going to sleep by going into Settings -> General -> Auto-Lock and setting it to Never.
Save further drain on the battery by switching off 3G, push notification, and Wi-Fi, turning down the screen brightness, etc.