how much is an iphone 4 if im with att and i already have a 2 yr contract?

my phone is brocken and i want a iphone 4 and i already have a contract so how much will it cost?

?2012-04-03T11:37:57Z

An iPhone 4 is $100 plus upgrade and taxes so you are looking at about $170. They will only let you do that if you are eligible for an upgrade.