iPhone overseas usage

[FerraraZ]

I have a Japanesse friend here in America whom is planning on going back to Japan after this semester is over. He is currently on Verizon but his family in Chicago recently all moved to AT&T. My question is how would his situation fare if he got an AT&T iPhone 4 and wanted to use the device overseas in Japan with providers like Softbank.

I'm just trying to convince him to get an iPhone since he loves his iPod and hates his current phone.

 

[kaerflog]

He can get an iPhone 4 right now but its not unlockable right now so its useless in Japan.
He can get a 3GS and they are all unlockable.
Alternatively, he can find an iPhone 4 thats still on the old baseband and those are unlockable. Those sells for like $600+ because it harder and harder to find.

 

[FerraraZ]

He can get an iPhone 4 right now but its not unlockable right now so its useless in Japan.
He can get a 3GS and they are all unlockable.
Alternatively, he can find an iPhone 4 thats still on the old baseband and those are unlockable. Those sells for like $600+ because it harder and harder to find.

But its still possible right? I know the 4.3.1 jailbreak just got released and the unlock is to follow.

 

[pm]

Yes, it would work if the iPhone 4 were to be unlocked.

As far as "the unlock is to follow" - all credit to the hackers of the DevTeam who do truly amazing things bypassing security and coming up with exploits, but the phrase "unlock is to follow" can mean months or even more... or never.

 

[Aikouka]

The unlock depends on the baseband that you're using. Not all 3GS phones that you may find can be unlocked... but that would depend on if you buy it used or new. For example, if I sold you my iPhone 3GS, the only way to unlock it would be to upgrade to the 6.15 baseband (I think that's the right number), as I'm currently at the unlockable 5.16.02 baseband. I think I was 5.15.04 (also unlockable) before I upgraded to 4.31 yesterday.

I believe Kaer is referring to new 3GS units though.

The problem with upgrading to 6.15 is that you cannot currently downgrade, and Apple will know that your iPhone has been upgraded unnaturally (6.15 does not prove an unlock or a hack).

 

[kaerflog]

The unlock depends on the baseband that you're using. Not all 3GS phones that you may find can be unlocked... but that would depend on if you buy it used or new. For example, if I sold you my iPhone 3GS, the only way to unlock it would be to upgrade to the 6.15 baseband (I think that's the right number), as I'm currently at the unlockable 5.16.02 baseband. I think I was 5.15.04 (also unlockable) before I upgraded to 4.31 yesterday.

I believe Kaer is referring to new 3GS units though.

The problem with upgrading to 6.15 is that you cannot currently downgrade, and Apple will know that your iPhone has been upgraded unnaturally (6.15 does not prove an unlock or a hack).

What you say is true but as I stated before, all 3GS are unlockable.
There is a risk using the 6.15 baseband but I've had one for months and its fine(and so for everybody else too). As for warranty, its useless if hes in Japan anyway.

Well, you can keep thinking there is an unlock for the IP4 "on the way" but its been "on the way" since nov 2010.
Thats when the 4.1 came out and they haven't release the unlock for anything 4.1 and higher.
But yes, Softbank uses GSM and their 3G is 2100 which is also compatible with all iPhones.