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∞'s Small Guide to Backgrounding (part 1: Regular apps)
In normal conditions (*), in iPhone OS 4.0, when Home is pressed, your app will go to the background but will NOT be kept running. It’ll be suspended, then resumed whenever the user gets back to it (whether via the Home screen, a URL being opened, or the new task switcher).
(*) Normal conditions are:
* You’re on iPhone 3GS or iPod touch 3rd gen or (presumably, but not Apple-announced) iPad when 4.x for it hits the scene this Sept.
* Your app is linked against (read: the Base SDK setting is) 4.0 or later.
* You haven’t opted out of backgrounding by adding the UIApplicationExitsOnSuspend key to Info.plist and setting it to boolean YES.
* You haven’t requested any particular background service. (See below.)
