Question: what is the difference between gsm and cdma unlocked?
Answer: Well GSM networks like US Mobile, T-Mobile, and AT&T use removable SIM cards. This means that unlocked phones from other American GSM carriers will work on US Mobile's network. On the other hand, Verizon and Sprint are CDMA carriers. CDMA carriers don't use SIM cards and most CDMA phones are locked into their network.