Recently Walmart has started a deal where you can buy an iPhone 5s for only $199. If you really wanted to, you can drop that price down lower by giving them your older devices of various types such as video games and other iPhones. The iPhone 5c will be only $29. Both of these models are 16GB and you have to buy a 2-year contract to go with your new iPhone.
Target is trying to get in the game as well with their new deal starting today where you can trade in a good-condition iPad 2 for at least $150 in-store credit. Not unlike Walmart, you can make that in-store credit grow by buying a brand new iPad once you trade your old one in. This means that you could buy a new iPad for only $220. Along with that deal, you can trade in your old smartphones for $50 extra than you normally would receive, as long as you plan to buy an iPhone 5s or 5c with a 2-year contract.