^^^This!
Full price Sprint iPhones are still locked. SIM free iPhones bought at the Apple store or online from Apple are unlocked. They will work on all four carriers.
Buy from anywhere other than Apple and you will have a phone locked to Sprint.
have you or anyone else been able to verify that the unlocked phone can be activated on Sprint, or will Sprint even give you a SIM card for the device?
I'm ready to switch from AT&T now, but don't want to purchase a device that will lock me to Sprint.