All I know is that when I bring my iPhone back to life the wifi symbol is not "there" and only then kicks back to life .. so no idea what you are all on about.
Yet if before you brought it back to life you were to open iTunes you would see the iPhone listed and could initiate a sync or backup. Only if within wifi range, naturally. How do you suppose iTunes does that, pixie dust?
I won't even get into the outrage there would be if all night long any emails received, etc. were being downloaded over cellular.
As for how this relates to the N4, it's simple: you
can force wifi to be truly off on the N4 when it's sleeping. You don't get that option with iOS as Apple has made that decision for you. You can also tell the N4 to not use wifi if the wifi doesn't have a good Internet connection. The iPhone will blindly switch from a perfectly good 3G/4G connection to a wifi connection that has no Internet access.
Mike