NetworkFinder
Instantly identify the provider of a US mobile number for free by entering the 10-digit number and clicking the search button.

Reverse Phone Search App on Google Play
This app offers a complimentary service for identifying unknown phone numbers by revealing the owner's name, caller information, location, mobile service provider, ...

North Carolina Number Discovery | PhoneNumbers.org
... services linked to discovering details about phone numbers, known as number lookup services or reverse mobile lookup. Services like Caller ID have advanced to ...