a.k.a. unlocked

If you've ever been told to buy an "unlocked" cell phone, unlocked means that it is recharged with prepaid cards instead of being on a monthly payment plan with a single carrier. This also means that the same cell phone can be used with carriers in other countries (assuming the frequency is the same) with a simple switch of the SIM card for under $40 in most cases. 

See also : GSM  
NetLingo Classification: Online Jargon