For folks looking to switch to Sprint soon, Amazon has a great deal on the 16GB Samsung Galaxy S4 that you will want to consider. They have dropped their price on the flagship device down to $99.99 on a new contract. This deal is for either the white or the black version. In comparison, the off contract price is still $649.99.
This offer is only for new contracts. If you are renewing your contract with Sprint the phone is still at the $199.99 price point.
Here are some links below to check out their offer.
Amazon: White 16GB Samsung Galaxy S4 from Sprint for $99.99 & Black 16GB Samsung Galaxy S4 from Sprint for $99.99