A:Answer It means that the phone is not "locked" to a single provider, such as AT&T or Verizon. AT&T, for example, will sell you an iPhone, but you have to agree to their (in my mind excessive) costs and be locked into a three year payment plan. You're not so much buying the hardware as you are buying a commitment to AT&T, with a discounted phone as incentive. An unlocked phone you can take to any provider (Patriot Mobil, for example) and they will set you up with a new phone number, or transfer an existing phone number.