AT&T Inc has stepped up its cellular rebranding strategy ahead of the launch of the new iPhone device next month. The firm has replaced all references to the Cingular Wireless brand with the AT&T name in its 1,800 retail outlets. AT&T is the exclusive US wireless partner for Apple’s iPhone device, which combines a mobile handset with a personal media player, and the firm is keen to see the AT&T brand introduced as widely as possible before its release. AT&T Inc took full control of Cingular Wireless in December 2006 when it completed its merger with its former partner in the venture, BellSouth. It is now the largest fixed line, internet and cellular operator in the US.