International iPhone question.

I'm going to Florida in a few weeks and I've been wanting an iPhone lately. I'm thinking I might buy one while I'm away if I can find one that'll end up cheaper with exchange rates n' whatnot. My question is if I get a sim-free iPhone and bring it home (To Ireland), will it work? Or is there any kind of region locking on them?

To get an iPhone here in the US is done two ways, one is getting it from AT&T under a 2 year contract, which will not happen to people visiting unless they have relatives doing them a favor, or buying the iPhone through eBay.

Since you're getting the iPhone here in the US, it's going to be locked to AT&T period unless you get a factory unlocked iPhone through eBay but you're better off getting them overseas since they jack up the prices.

With that in mind, if you do get an iPhone you need to make sure that it can be jailbroken, AND then have the proper baseband to be software unlocked. eBay can make this easier for you if you just look for unlocked iPhones.

If you do get an unlocked iPhone, then yes, you can use it back at home. All you gotta do is pop in the SIM, and you're good to go. If you want an iPhone 4, be aware that is uses Micro Sims, a normal SIM card will not work.