AT&T was first to get the iPhone, yet it won't support iPhone Handoff

Apple's new ability to have one phone number and switch between two iPhones is spreading to more carriers, but AT&T doesn't seem to care.
You won't have to decide on just one iPhone with the new iPhone Handoff.
It was actually Cingular who was the only carrier Steve Jobs could get to take the iPhone, and also surrender the control carriers had back around 2007. But AT&T bought Cingular before the iPhone launch and so was the exclusive carrier for the device that revolutionized cellphones