I know this is probably a very stupid question, but I'm thinking of buying a fitness tracker for the first time (Garmin) and just wondering how the GPS/Internet connection works. I assume it's free and you don't have to buy data or connect it to your smartphone data plan? Also, I'm currently on vacation in Spain (normally live in the UK) so it wont make any difference will it, or should I wait until I'm back in the UK?