what carrier can i use if i unlock an iphone?

[gerardo]

what companies can i go with if i unlock an iphone

 

[jocoolguy]

You can use any GSM Network Sim card,You can swap to any carriers in your country or if you go to other country means get the GSM Sim card there and activate it use it,these all done by only unlock it as you said.Get the Unlock service for Apple's I-Phones at here
Prounlocking and Unlock it.