AT&T on Tuesday finally made good on its promise to launch a mobile banking application, with the help of an Atlanta-based startup.

The launch comes one year after AT&T first announced plans to introduce mobile banking to its subscribers with the help of Firethorn Holdings, a mobile banking service startup,

But the largest carrier in the U.S. was able to sign up just two large banks, Wachovia, the forurth largest bank in the U.S., and SunTrust Banks, the ninth largest, for its service launch, demonstrating one of the major hurdles that mobile banking faces, an analyst said.

"After a year AT&T gains the endorsement of just two big banks, which indicates that many banks are not yet comfortable with the progress of security and the integration steps that must happen," Forrester Research analyst Charles Golvin said.

AT&T has mobile banking relationships with a number of much smaller banks including BancorpSouth, FirstBank, and Synovus. Regions Financial, America First Credit Union, and Arvest Bank Group have also signed mobile banking agreements with AT&T.

Mobile banking, the ability to check balances, pay bills, or transfer funds on cell phones, has emerged at glacial speed in the United States in part because nationwide banks have been slow to adopt it, but also because consumers are not exactly clamoring for it, Mr. Golvin said.

Mobile banking does not address an urgent consumer need, he said, and one carrier representing two large banks may not create enough traction to drive significant penetration of mobile banking in the U.S.

But AT&T plans to spend heavily on marketing in an effort to spur user adoption and bring more of the major, national banks into the mobile banking fold.

"The technology is in place now and we are getting the banks on board, so the job now is to drive awareness," said Kelly Buday, spokeswoman for Atlanta-based Firethorn.

Five-year-old Firethorn has taken a somewhat unique approach to building a business around mobile banking. The company is set up as a hosted service that acts as a kind of clearinghouse blending the needs of three very demanding communities: the cell phone industry, the banking industry, and the mobile service customer.

AT&T's mobile banking application is now available for download on more than 30 of the carrier's handsets. Starting later this year the mobile banking application will be pre-loaded on all future AT&T handsets.