Can I use my iPhone 6 in Japan?

Hi, I will be attending university in Japan as a full-time student (4 years). Currently I have an unlocked iPhone 6 so I am wondering if I can use that in Japan? If so, what carrier do you recommend? I've read that IIJmio is really cheap so I might buy that. I really don't want to spend 10,000 yen/month on a contract phone.
I will be living in Shinjuku, Tokyo.

Thanks!!

The only decent MVNO is UQ mobile and it does not support iPhones. If you go with another one such as iijmio, you will probably be very disappointed with the data speeds.

If you read Japanese, see http://kakuyasu-sim.jp/

I have service with iijmio and no complaints at all (except for the fact that you need a credit [not debit!] card for paying).
Maybe I'm not very picky about data speeds? I don't know, it seems to work fine for me.

they request you have a credit card.

Thanks everyone!!
I think I'm going to try IIJmio so I don't have to buy a new phone. and also make a new credit card just to get the SIM card... ugh D: