Apple has posted an FAQ (frequently asked questions) page concerning the new SIM-free (i.e. unlocked) iPhone 3GS and iPhone 4 they're selling for the first time in international Apple Store like UK, France, and Canada.
Bottom line? They're really, truly, 100% unlocked and will work on any GSM carrier for which you have a miniSIM (iPhone 3GS) or microSIM (iPhone 4). You'll pay full price for them, of course, but for those who absolutely don't want a contract, or for frequent international travelers, this is huge.
(Note: No T-Mobile US 3G. Sorry folks, even though iPhone 4 is pentaband, T-Mobile's 3G band isn't supported. It hurts. Sorry).
Here's the cover:
Buy your iPhone from Apple commitment-free.
It works with the carrier of your choice. Buy your iPhone from the Apple Online Store and choose your own GSM carrier. You can change carriers at any time.
It's easy to set up. Get a compatible SIM (iPhone 3GS) or micro-SIM card (iPhone 4) and select a plan from the carrier of your choice. Then insert the card and set up your iPhone using iTunes on your Mac or PC. With a few clicks, you can start making calls.
It works internationally. Because this iPhone is commitment-free, you can purchase a micro-SIM or SIM card and service from a local carrier at your destination. Or check with your home carrier regarding international roaming charges.
Full FAQ after the break!
Does iPhone work with any SIM card or carrier worldwide?
iPhone 3GS works with SIM cards and iPhone 4 works with micro-SIM cards from compatible carriers, including prepaid cards. Non-GSM carrier networks do not support iPhone. Availability of 3G data depends on carrier support for the radio frequencies used by iPhone.
Where can I get a SIM or micro-SIM card?
You can get a SIM or micro-SIM card from any carrier offering iPhone plans.
How do I get started using iPhone to place and receive calls?
First, insert an activated SIM or micro-SIM card from a compatible carrier. Then connect your iPhone to your computer and open iTunes to complete set up.
Do I need an iPhone-specific service plan?
iPhone may require large amounts of data usage. Please contact your carrier to ensure that you have an appropriate service plan to support iPhone.
Do I need to commit to a long-term contract for my iPhone?
Buying a commitment-free iPhone from the Apple Online Store allows you choose your own carrier and change carriers at any time. iPhone may also be available at a reduced initial price with a contract directly from your wireless carrier.
Does iPhone support tethering?
Yes. You can share the fast 3G connection on your iPhone with your Mac or PC and connect to the Internet from just about anywhere — no Wi-Fi required. Contact your carrier for details.
Are iPhone 4 and iPad micro-SIM cards interchangeable?
No. Your iPad micro-SIM card will not work with your iPhone.
Will all iPhone features work with my carrier?
Visual Voicemail requires carrier support and may not function on your carrier's network. Please read this Support article or contact your carrier for more details.
Why does the price of iPhone from the Apple Online Store differ from its price from a carrier?
Carriers typically sell the iPhone with a contract that subsidizes the initial purchase price of the phone. By purchasing your iPhone without a contract, you can use any SIM or micro-SIM card from a compatible carrier, including your current one.
Can I use my iPhone outside my home country?
Yes. iPhone is enabled to work on carrier networks using GSM around the world. Because the iPhone sold by the Apple Online Store is commitment-free, you can purchase a SIM or micro-SIM card and service from a local carrier at your destination. Or check with your home carrier regarding international roaming charges.
If I buy iPhone from this Apple Online Store, can I ship it to another country?
No. Orders placed through this Apple Online Store can be shipped only within the country of purchase. You can also shop for friends and family in countries where iPhone is sold. Just visit the local store of the country where you want your products delivered.