Cell phone use in Japan

Data and voice roaming rates are unrealistically high to use my existing cell phone plan there. Does anybody have any experience with putting a GSM sim card from a local carrier in an unlocked phone?

Optimally, I care more about the data so I can take advantage of web surfing and GPS maps on my iPhone.

Thanks

You can rent a Softbank sim card at the airport but be warned the cost of data is very high. They will warn you this actually and advise that you do not use data.

I do not believe there is a cheap way you will be able to use your iPhone in Japan to its full potential short of using someone else's contract sim.

Don't know if this a complete answer, but if you're interested in data over your iPhone, the best way would be to turn of data roaming, and go with wifi. You should be able to find several spots in most cities in Japan.

If you're traveling to the countryside it may be a little more difficult to find free wifi.

As the previous poster said data is extremely expensive unless you have a hodai (unlimited) data plan, and I don't remember that being an option with the rental sim card.

Thank you both for your responses. I guess as a side question do you know of any WiFi subscriptions that are offered so I don't have to hunt all over the place for unlocked access?

http://www.g-call.com/e/phone/data/index.php

they offer a usb modem that uses the mobile network for data, it apparently comes with a sim card

http://www.jcrcorp.com/mobile/3g_unlim_data.htm

I am getting an unlocked 3G/GSM Japanese cell phone.
I know that making/getting calls works just fine but how about text messaging (or email) and internet browsing? Would I be able to use them with no problem or I will not be able to use it at all?

That's some very good information you have provided there eXstnZ. I had no idea that level of service was offered by any company. Data normally costs a small fortune.
rpiyokiti assuming you mean you are getting the unlocked phone for use in the US then your calls and text messages will work just fine.
Emails and anything else internet based (including the many apps that will be on it) will not work at all. Quite common as these features are locked to specific usim's and internet settings cannot be changed.

There is one other thing I should mention. Check how the phone has been unlocked by the seller. If it has been software unlocked then the information I have provided is good.
If it will be unlocked via a hypersim or similar then there is no telling how well the basic features will even function and you may find that even multimedia will not work.
You would have to do a bit of research into the phone you are getting.
http://www.howardforums.com/forumdisplay.php?f=418 might be helpful for that.

I recently visited Japan and took my IPOD which has a WIFI connection. I was able to find many Wifi "FREE SPOTs" just walking around in Tokyo (Shibuya and Shinjuku for example.) Also I stayed at Comfort Hotels in Osaka, Fukuoka, Nagasaki and Hiroshima and all had free Wifi in the lobby and rooms.