sberman is correct. If you purchased your phone in the US with an AppleCare plan, it WON'T be valid in Japan, if that is where you live and use the phone. If you have an issue with the phone, you'll need to come back to the US for service. It's NEVER a good idea to buy an iPhone in a country you don't live. If you did this, you'd be best advised to return the phone to Apple for refund and buy the phone when you get back home. If you are unwilling to do that, cancel the AppleCare plan as paying for it would be pretty much a waste of money.