Unlocked iPhone 4 now available at Apple Stores

Buying an unlocked version of the iPhone is now easier than ever.

Apple has decided to make the device available at its own retail store locations, in addition to the models that are locked into service agreements with AT&T and Verizon.

It’s not cheap, though. For the privilege to be able to run any mobile service you want, you’ll have to fork over $650 for the 16 GB version, or a whopping $750 for the 32 GB version.

The unlocked version of the iPhone 4 can only run on networks powered by GSM technology, which means in the US, only carriers AT&T and T-Mobile are compatible.

So in other words, the only reason most US consumers would want to buy an unlocked iPhone 4 is if they wanted to get T-Mobile service with it. Well, that, or they already have an AT&T service agreement and are not eligible to upgrade.

The unlocked feature is more of an appeal to consumers who live abroad or who do a lot of overseas traveling, as it means users are free to swap between carriers in different countries.

In other words, the addition of the unlocked iPhone 4 is likely to appeal only to a niche crowd.