I’ve jailbroken my 3G iPhone so I can use it in Europe. AT&T can’t seem to figure out how to make their service work over here (no matter how many times I call and they tell me I’ll be able to use it) so I took it upon myself to do it. With the tools from the iphone-dev team it’s a snap. Turns out the iPhone works great here.

It will even do WiFi channels 12 and 13, verboten in the US, but loved by the Euros – possibly because our eqiupment can’t pick them up. Who would have thought Europeans would be exclusionary? So while the cafes and hotels are unapologetic to the legions of North Americans (yes, Canada, you’re screwed too) who can’t connect, I surf happily, albeit limitedly.

The first thing you’ll need to do when you get here is to grab a new SIM card. Check rates before you arrive and you can probably grab your choice at the airport in many cases. But keep in mind that roaming to a different country can get expensive, so don’t put a lot of money on the card unless you think you’ll use it all in that country. Since data and calling costs vary from country to country, you’ll have to figure out how much is right for you.

There are also some quirks to European networks. For example, it’s cheaper to call the US than Ireland from some Irish carriers like Vodaphone. Here’s another quirk: The O2 network in Ireland will charge you between twice and infinitely as much as you should pay. After “topping up” (adding money to the SIM) by 10 Euro, I visited the O2 website – 100kB, according to O2 themselves – and all my credit was gone. After topping up again, I used 5 Euro while my phone was off.

Something I’ve run into here a couple of times is that the SIM cards don’t work on the iPhone for data. I finally figured out why and after a few configuration changes, I was up and running. It turns out that there’s something called “APN settings” which consist of an APN name, username and password – all of which are well known, and all of which are different for each network. If you don’t have these, you can’t get online. There are lots of tutorials out there, but most of them are complicated or didn’t work for me. So here’s how I did it.

1. After you’ve got the SIM card in the iPhone, go to Settings -> General -> Network.
2. If you have the Cellular Data Network menu, enter your details there (google for your SIM card’s APN settings if they didn’t come with the package) and you should be set.
3. If you don’t have that, don’t fret. Turn your phone off, put in your old SIM card, and power it on. You should now have the menu. What use is the menu on the old network?
4. WARNING: RISK INVOLVED. But I’m guessing if you’ve jailbroken your iPhone you don’t care about that. So pop out your old SIM while the phone is still on and replace it with the new SIM card.
5. Configure your new SIM’s APN settings – you should see the 3G icon appear. If not, you may have to restart your phone.
6. Now you should be on the Internet! Impress your friends and the locals!
7. Don’t contact me if you have problems, this worked for me and that’s all I know.

FYI, for a pay-as-you-go SIM card on O2 UK, you have to change the APN to payandgo.o2.co.uk – leave the login and password the same (vertigo/password).