O2 Phone upgrade, compatable with satnav?

[GSDog]

Iam due an upgrade on my o2 contract, i have been looking at the following phones:

Nokia N70 - Favourite
Motorola V3x
O2 XDA mini s / Exec.

I have since heard about the use of satnav on mobile phones, Im not sure on the O2 XDA's as i will be using it as a phone mostly (size), but i am growing towards the nokia N70.

What would i need to do/buy to enable Satnav on the Nokia n70, i have heard tomtom do software? And what is the satnav like on the phone? is it simply for road use, or can it be used as GPS (for walking).

I was originally going to get the V3X as it is 3G, but i have heard a few bad reviews on the phone. And now the option of satnav is really sounding good!

Any help much appreciated.

 

[GSDog]

ok thanx 4 the info, iv gone or the N70, should get it next week. I have been looking into the tomtom kits they do for around £180, where you get the bluetooth reciever, mini SD card with the software installed, and chargers etc.
I think im going to buy a reciever seperate and just try to get the software on it own, because i have a card reader/writer, so im hoping to write the software straight onto a card of my own. I believe they come with a 128mb card, which i wouldnt use anyway as its too small.

Does anyone know where you can buy the tomtom mobile5 software alone?