GPS mobile phones - need a sim card?

I'm considering the purchase of a mobile phone with GPS capability for use in Europe later this year.

Do I need a sim card for each country I pass through for the GPS position finder function to work?

As rayonline points out, Nokia has free gps maps that work offline without a sim card. I have a cheap Nokia E5 and so far it has been the most amazing travel gadget. The maps work extremely well, the walk and drive navigation were a life saver when I used it in the crowded streets of Bangkok. For walk navigation, it accurately gave the distance and expected time of arrival to the destination as well as other useful information on points of interest.

The Nokia maps will work fine without a sim card, however, I can also confirm that the initial lock time of the gps will be much slower. On an overcast day, it would take about 3mins, and if you are unluncky, as much as 10mins to get a decent satellite lock. Once you have the satellite lock, it will work perfectly.

It's for that reason (the need for 3G/SIM) that I ended up splashing out and purchased CoPilot Oz Pan European maps for my Smartphone. Best investment I ever made for driving through a lot of W and Central Europe.

Do I need a sim card for each country I pass through for the GPS

To answer the actual question....
Sometimes yes, sometimes no.
Across (especially) Eastern Europe, many sims only work in the country they're purchased in.
Once you cross the border - they go dead.

Sim card/online functions of GPS systems are

• A-GPS; assisted GPS. the phone downloads sat info via sim card/data link. Without this GPS will still work but can take considerably longer to get a fix on the satellites (to display your actual position).

• Maps: if you only need a map of the place with you GPS position there is offline maps available these days in many different forms. Even google maps allows you to save limited size areas to your device nowadays, Others like OSM (open street map) allow entire countries/regions to be downloaded. So if you use your GPS as map with position on it, no need really for dsta connection/sim card.

• Routing; if you want to use it like a real car GPS system with routing and instructions you will usually have to buy that (apart from Nokia maps on ols symbian OS phones, their WP7 phones don't seem to have that function yet), see above.
  Some systems need data link/simcard for routing, some don't
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Thanks, all. In the end I've decided to lease a vehicle with a built in GPS and leave telephone conversations to Skype, as I'll be carrying a netbook.

It's all a little different from when I started travelling and steamships, aerogrammes, bank drafts, travellers cheques and mail pickups at Post Restante or American Express offices were the norm.

I do miss the ships.