"Jonathan Zdziarski (aka NerveGas), recently wrote about the kill switch that is buried within the iPhone. This kill switch has been purported to do everything except wash your dishes. NerveGas decided to write more at length about what it does, and doesn't do at his site. You can read his full article here.
The following is an excerpt:
"The locationd cache, stored in /var/root/Library/Caches/locationd/, includes a cached list of unauthorized applications fetched from a URL on Apple's servers during GPS fix. Only a list is downloaded; it doesn't "tell Apple" what applications you are running. We do not know just how active this mechanism will be in the future. It could vaporize applications, but so far we can only make it kill the ones using the GPS. We don't know what else it might do....This definitely warrants some questions to Apple, and merits further research to determine what else, if anything, this means for iPhone users."
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