I have been playing around with data available from the iPhone (and also separately visualizing Map data).

I came across a project, iPhoneTracker which was done to show iPhone users the kind of data that the iPhone collects about a users travel and whereabouts. I downloaded the app and ran it. Looks like about a complete history since I activated the phone… The interesting thing for me was that this app did not collect the data from my phone directly but rather from my computer.

iPhone location history from my iPhone