Iphone 4/5 ?

Hello,

I will be going to Japan, on WH visa starting next August.
My old cellphone just died, and as a replacement, I was thinking about buying an Iphone, but as I don't have so muche money right now, I'm not sure it would be worth it, if I can only use it for the few months before I go to japan...

Question is, I highly doubt an Iphone4 purchased in Europe would work in Japan, but just in case, would it?
On the other hand, as a WH-visa holder, would I be able to buy an Iphone in Japan?
And, if I can, would it work in Europe?

Same questions for androids?
Are there any Smartphones that would work in both japan and europe?

thank you

My old cellphone just died, and as a replacement, I was thinking about buying an Iphone, but as I don't have so muche money right now, I'm not sure it would be worth it, if I can only use it for the few months before I go to japan...

It probably would not be worth it if you don't have a lot of money as most likely the phone will be expensive, the plan will be expensive, and cancelling the plan after a few months will be expensive. Consider waiting until you get to Japan to get one on contract here.

Question is, I highly doubt an Iphone4 purchased in Europe would work in Japan, but just in case, would it?

Yes, assuming it is unlocked. However you would have to go through a service reseller rather than Softbank for service. Docomo may also have a contract plan available for unlocked smartphones by the time you come as well. Here's one reseller that looks to have good plans with unlimited data:

http://www.bmobile.ne.jp/lineup.html

On the other hand, as a WH-visa holder, would I be able to buy an Iphone in Japan?

Yes, you should be able to. Some phone outlets may be reluctant so sell you one since you need to sign a 2 year contract, but you should be able to shop around until you find someone who will sell it to you.

And, if I can, would it work in Europe?

Yes, but you would have to unlock it. Note that Softbank will not unlock it for you.

Same questions for androids?

Generally the same answers apply to android phones.

Are there any Smartphones that would work in both japan and europe?

The ones that operate on the 2100mhz 3g spectrum will operate in Japan. GSM and 4g networks however are not available in Japan.