Of course, there are some stipulations, but if you qualify, you could “save” significantly on an iPhone Duo—as much as $1,200, knocking the price to $800 (keep reading, there’s a catch). Here are some of the potential deals we found. Shipping times are stretching into January, so it may be a while before you can get your hands on an iPhone Duo, even with one of these offers. Save $1,200 on an iPhone Duo at T-Mobile If you sign up for an Experience Beyond plan, T-Mobile will credit you $1,200.