Apple Store employees can now unlock iPhone 4 phones specifically made for AT&T by selling them as Device Only at the checkout counter.

9 to 5 Mac reported that Apple Store employees can now use an AT&T SKU and unlock the phone in case of shortage of the official unlocked GSM SKUs.

An Apple Store employee has to ring the phone at the checkout as Device Only and the system will unlock the phone. The customers will have to shell out $649 for 16GB and $749 for 32GB version.

Apple officially launched unlocked iPhone 4 in black and white colors. The phones come sans a micro-SIM card and can be run on GSM networks domestically and internationally.

Recently T-Mobile revealed that it has over a million unlocked iPhones on its network. Most of the iPhones on T-Mobile network are pre-iPhone 4 models. However to run iPhone 4 on T-Mobile users will have to manually cut the SIM cards as iPhone 4 uses a micro-SIM and T-Mobile does not offer a micro-SIM variant.

Apple's next rendition of iPhone, the iPhone 5, which is due in September, is rumored to be a SIM-less phone with 2 to 3 inbuilt antennas which will make it both GSM and CDMA compatible.

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