I am looking into buying a used smartphone but I have done my research and looked that one has to be care-full.
For starters on the CDMA Networks like Verizon one has to check the ESN to make sure it is not "locked, stolen etc."
So It leads me to my question:
Since GSM phones work with SIM cards can they be locked as well (with there IMEI #)? Or can I just insert a different card and make it work?
And if there locked I guess the best thing to do is check it with a retail store we want to activate with right?