So as of recently Ive been wanting a new cell phone. I have at&t. Im nowhere near my time for a upgrade. Im using this old samsun flip phone from like 2003 because my nokia smartphone broke a few months ago. So I thought it might just be a good idea to see if I could get a phone from japan and use it here. they generally have better ones than that are available on the us market (besides Iphone 4). If the phone has already been unlocked. Cant it receive calls use internet and send txt in the usa using my at&t sim card work in the phone? also whats this i hear about a hypersim card? anyone have any experience with this kinda of setup? any specific ones you woudl suggest? I dont wana spend more than like 500sih$ Thanx