Currently, this thread is about TomTom Mobile 5 for the Nokia 6620 - the "Mobile" product name refers exclusively to the version that runs on Nokia symbian OS. TomTom also has the "Navigator' product line that runs on Palm and PPC.
To get the gps navigation running on nokia you need three things:
A Nokia Symbian phone.
The TomTom software (which comes with maps.)
The GPS receiver
Now, you can skip the gps receiver part if you just want a MS Streets and Trips type experience, and have it just show you the directions (though options.. Advanced Planning in TomTom) but really, what's the point? you could print out some google maps ahead of time and save yourself the cost of everything else.
Now the tricky part:
To navigate in North America with a Symbian phone, you have to buy two packages! that's right, TomTom does not sell the Mobile software with North American maps... so, you have to buy TomTom Mobile 5 with some European maps (packages vary), then buy TomTom Navigator.
After you've got TomTom Mobile running on your phone (and have at least one map activated), it gets a little tricky. You need to put the maps from Navigator onto your MMC card for use on your Symbian phone.... Since the Navigator software was meant to run on Palm or PPC, it won't install any maps without Palm or ActiveSync conduit software installed on your home pc.
Side Note: This is Not an issue for me ( I have a Palm TX that I run TomTom on as well), but if you're in a bind, you can download the conduit software from Palm, and install it even if you don't have a Palm unit....
So after you get the palm conduit installed, you need to install maps somewhere - there is an "Other Location" option in the map install - put the map somewhere on your harddrive, and transfer it to your MMC afterwards.
Make sure to copy the whole folder to the root of the MMC or TomTom Mobile won't find it. (This kind of pees me off, cause I like to keep my folder structure neat.)
Throw the MMC back in the phone, start up TomTom, and select options..preferences..change maps - the new maps from north american should be visible.
For those in Canada - TomTom does have fairly decent map coverage, but expect POIs about 2.5 years out of date, as well as any road newer than 3.5 years to be off in non-central locations (ie. out of the cities)
Cheers!
/O