This article will aim to help a little bit the guys who try to understand/find tracks on a Tomtom GPS. The model being investigated is a Tomtom Rider 2, 2010.
First of all, extract the SD Card, and then plug it to a safe/secured computer.
At the root of the card, you'll find a file called settings.dat. You may open it using gVim. It contains the list of the cell phones that have been associated to the GPS (via Bluetooth connection).
The syntax is quite simple, apart of a bit of garbage within the file: the phone name, and its MAC address (the separator is a simple comma).
Then the folder named "contacts" is quite interesting. It contains 3 files: called.txt, callers.txt, contacts.txt.
Those filenames are pretty relevant to the data the corresponding files contain. Furthermore, the data is in plain-text!
AFAIK, the "contacts.txt" file will only contain data if the cellphone contacts have been synchronized with the GPS (it does automatically offer synchronization the first time it's being associated via Bluetooth).
Then, depending on the principal map that has been used on the GPS, you'll find a folder named accordingly. For instance, here, the folder's name is "france".
Inside this folder, there are several files. One of them will probably be quite important to the analyst: MapSettings.cfg.
It contains the addresses that have been typed and triggered a roadmap calculation.
The file is in plain-text. It appears that the addresses are being chronologically printed.
Quite strange, at the end of the same file, there is the name and MAC address of the headset that has been used with the Tomtom (could be useful, who knows). Here it is: TomTom Headset (scala-rider),00:0A:9B:20:AE:99.
To those who may be interested, here is the whole list of files that are stored on the SD card:
I hope this helps and will tell people how easy it is to find personal information about them...