A quick question-and-answer about the best way to roam across the world using multiple local SIM cards -- this question was about europe, but it's applicable for most countries.
I just got a free GSM phone from AT&T (Samsung A437) that is quad band. I unlocked it successfully and now need a SIM to use abroad. I'm researching the best SIM to get in order to allow my wife to call me when I travel and allow me to call her.
Any thoughts on International SIM card vs. ountry pre-paid SIMs? I'll be travelling to Western Europe mostly and also Japan.
Thanks for your thoughts!!!
so-called "international" SIM cards are pretty much a ripoff (as is roaming!) :)
the best way to go is to buy a SIM card locally for each country that you're in, then you can buy refills at most tobacco shops or corner markets. to buy the SIM, you can usually buy those at corner markets as well. your passport ID may be required when you buy them.
japan is the one country that (as far as i can tell) doesn't sell sim cards to foreigners. you can roam here using a roaming-enabled european sim card. i recommend using a Vodafone sim card from the UK -- i was able to get on the Japanese GSM network using this. given the high dollar/pound exchange rate, i only recommend using this solution for text messaging (which is like 50p or something per message)
to have your wife reach your new numbers, one easy solution is to register for a Skype account, buy a SkypeIn number in your area code, set the account to auto-refill with PayPal. then whenever you get a new SIM card/number, go to your settings in Skype and tell it to forward all calls to that number.
then when your wife calls the local number, it will forward to your phone number, and then the international rate charged to your account is the Skype rate for that country, which is almost as cheap as it gets. see http://www.skype.com/prices/callrates/ for skype call rates.
this is the solution i did on my trip, and it worked pretty well. you can roam in europe with SIM cards from other european countries, but the hassle is you can't buy recharge cards (for exampel) for the UK when you're in France, even if both countries have a Vodafone company there.