GPX files (gps exchange format)
GPX files contain a very detailed recording of where you have been on your track, including any off-road locations. GPX files become tracks after import.
Using GPX files
There are several things you can do with your GPX file:
Note: While viewing your recording, you may notice that the recorded GPS locations do not always correspond with the roads. This can happen for several reasons. Firstly, your device tries to keep the files small and this can cause a slight loss of data precision. Secondly, your device records the actual data from the GPS chip for an accurate representation of where you’ve been, rather than what you see on your screen. Thirdly, the software with which you view the recording may have the maps misaligned.
ITN files (TomTom's own Itinerary file format)
An ITN file contains less detail than a GPX file. An ITN file can contain a maximum of 255 locations which is enough to recreate a route accurately. ITN files become routes after import.
Using ITN files
There are several things you can do with your ITN file:
Note: Routes can be imported but cannot exported.