If you haven’t heard yet, your iPhone creates a record of all the places you go, and the information is stored in a database on your computer whenever you sync with iTunes.
See here for more information, and an application that will show you a map with all the locations you’ve ever visited with your iPhone:
Here’s an example screenshot of the iPhone Tracker application:
Apple doesn’t seem to be sending this information anywhere, but really, they shouldn’t be storing this much of this kind of information unencrypted in the first place.
The first thing you should do is enable encrypted iPhone backups so that other users and applications on your computer can’t access this information. I’ve been doing this for a while.
iPhoneTracker for OS X Leopard (10.5) and 32-bit Processors
If you have an older Mac with a 32-bit Intel Core Duo processor which can’t run the 64-bit version of the application on Pete Warden’s site, you will get this message:
If you are running Mac OS X Leopard (10.5) you will see this message:
“You cannot use this version of the application iPhoneTracker with this version of Mac OS X”
You can download and try run this 32-bit version I made for Mac OS X Leopard (10.5):
MD5 fingerprint for the zip file is: 3977c24e07019e23c987337f9342e684
And this 32-bit build I made for Snow Leopard (10.6):
MD5 fingerprint for the zip file is: f8d2b4ccf107198a22aef655765d9654
For the geeks, you can get my modified version of Pete Warden’s source at this github repository:
Update: Combined with the fact that police officers in some areas are copying the content from cellphones of people stopped for traffic offences, it gets scarier:
Update 3: The original version of iPhoneTracker now supports 32-bit and PPC machines, and presumably OS X Leopard. You shouldn’t need my custom build any more.
Update 4: I made a build that increases the time and location accuracy. I’m not sure how useful this is, but here you go: iPhoneTracker_32bit_higher_accuracy.zip
Update 5: Apple heard, and have released a version of iOS that fixes some of the security problems:
(Hat tip Andrew Hedges)