Updated: June 14, 2011

As earlier reports predicted, Apple has begun selling unlocked (GSM) iPhone 4’s this morning on the Apple Store.

If you don’t want a multiyear service contract or if you prefer to use a local carrier when traveling abroad, the unlocked iPhone 4 is the best choice. It arrives without a micro-SIM card, so you’ll need an active micro-SIM card from any supported GSM carrier worldwide.

The unlocked iPhone 4’s start at $649 for the 16GB and $749 for the 32GB.

Unlocked iPhone’s have been available internationally for some time, but the carrier market in the U.S. is such that it’s not possible to transfer between companies due to a lack of a compatible 3G service. With iPhone 4’s available with AT&T, T-Mobile and Verizon, now customers will have the option of purchasing an iPhone 4 and inserting a pre-paid SIM card from the carrier of their choice.