Singular Wireless

AT&T Mobility LLC (usually branded "AT&T,"[2] and formerly named Cingular Wireless LLC) is the wholly owned wireless subsidiary of AT&T Inc. AT&T Mobility is the largest mobile phone company in the United States and it also operates in Puerto Rico and the United States Virgin Islands. AT&T Mobility has 63.7 million subscribers as of the end of the second quarter for 2007, and claims to operate the largest digital voice and data network in the United States.[3]
Formerly a joint venture between SBC Communications and BellSouth, Cingular Wireless soon acquired the old AT&T Wireless; SBC later acquired the original AT&T and rebranded as "the new AT&T". Cingular became wholly-owned by the new AT&T in December 2006 as a result of AT&T's acquisition of BellSouth.
The service is now branded as Wireless from AT&T or sometimes simply AT&T. Renaming on a corporate level occurred immediately, and consumer branding changed to "AT&T," or a variant thereof. Until all regulatory filings are approved, however, and public awareness is fostered, the "Cingular" brand will continue to be used in store signage and media advertisements during a dual-branded transition, expected to last several months. This process began January 15, 2007.[4] It completed in late June, just prior to the rollout of the Apple iPhone.
Among the services that AT&T aggressively promotes is its "Rollover" service, allowing customers to keep unused minutes from month to month on a twelve-month rolling cycle on its popular "Nation" nationwide plans. Beginning in July 2007, AT&T Mobility now allows its AT&T Unity plan users to have "Rollover", a service which was exclusive to the "Nation" plans.