Can i switch either my sprint iPhone 4, or my att i phone 4 to boost mobile?

I have 2 iphones, one from sprint and one from att. They are to expensive for me so i want to get them switched to boost mobile. Are either of the networks compatible with boost mobile? If not is there anyway i can make them compatible?

Sprint uses CDMA towers, att uses GSM. Call boost and see which is compatiable with their towers and use that one.