Can a sprint iphone be unlocked so an AT&T simcard can work with it? Is there absolutely any way?

Can a sprint iphone be unlocked so an AT&T simcard can work with it? Is there absolutely any way?

Many claim to have done this. Especially those selling the software, but I don't believe it's possible yet.
https://discussions.apple.com/...7#24266397
Besides, the unlock would have to be very thorough and the phone would have to be dual band capable. ATT runs on GSM like Tmobile. Big Red and Sprint run on CDMA signals. It'd have to be a 4s and up--if you could even get it unlocked. Might be better to sell and by an ATT compatible instead. Best luck.