You guys are confusing the OP please don't post if you don't know the answer. Sprint iPhones are indeed GSM & CDMA, all the new iPhones are able to use GSM. Any iPhone activated on or after 11/11/2011 will be sim locked at time of activation and there is NO FIRMWARE update that will ever lock that sim. However any iPhone activated before 11/11/2011 comes factory unlocked for INTERNATIONAL use ONLY!! I did however run into an issue where one of my 5 were locked, I called in and they are still working on it :/