As of June 15, Apple quietly but surely started selling unlocked iPhones in the U.S. for the first time via its websites and stores, priced at $649 and $749.

No longer do users have to rely on hackers to unlock the iPhones for use in other countries.

Of course, the buyer needs to buy a SIM (Subscriber Identity Module) card to activate the phone. But no biggie, as the unlocked version (which is exactly the same as the ones sold for use with AT&T) don't require a two-year contract.

Only the Apple stores will sell the unlocked phones, not AT&T, which also doesn't allow customers to unlock older iPhones.

The only other U.S. carrier that is compatible with the iPhone besides AT&T is T-Mobile U.S., which provides only phone calls and limited data speed, not to mention their 3G wireless high-speed data network isn't compatible with the phone.

Apple already sells unlocked iPhones in other countries where the phone has been released. AT&T also sells no-contract iPhone 4s that are locked, priced at $649 and $749.