A new green Parkmobile sign is mounted on the pay kiosk at Power Alley and Riverfront Parkway. The new parkmobile app parking system for will be managed by CARTA.

Gregg Dwyer of Kennesaw, Ga., says he uses his cell phone for lots of activities so using it to pay for parking is a natural.

"I'd do this everywhere," he said Friday at a downtown Chattanooga parking lot during a visit to the city.

CARTA has started a new service at four downtown lots and one garage in which motorists can use their cell phones to pay to park. It's part of a larger initiative to ease central-city parking problems.

"This is a step in the right direction," said Chattanooga Mayor Ron Littlefield as the pay-by-phone parking service was kicked off. "It's one additional step making it easy to do business downtown."

The technology from Atlanta-based Parkmobile USA allows motorists to charge parking fees to their credit cards. Motorists can register through the company or download an app.

Laurens Eckelboom, Parkmobile USA's executive vice president for marketing, said Chattanooga is the first city in Tennessee to implement the service.

He said signs at parking stations will help patrons use the new technology, which is also offered in Atlanta, Washington, D.C, Boston, Greenville, S.C., and other cities.

Eckelboom said motorists pay a 35-cent convenience fee per transaction.

"It's a flat fee," he said, which doesn't change whether the cost to park is $1 or $5.

Brent Matthews, CARTA's parking director, said the service moves the city forward in the use of technology. It's a help for people who don't have change or don't want to wait in line to pay.

The service will send an alert to the cell phone 15 minutes before a motorists' parking time runs out, Matthews said. The user can add on more time without having to return to the parking lot, he said.

City Councilman Manny Rico termed the new service "user friendly."

"You don't have to worry about having money," he said.

More downtown parking lots, including those run by Republic Parking System, are slated to start using the technology in four to eight weeks, Eckelboom said. Between 2,500 and 3,000 parking spaces in the central city could be available for the service by late summer, he said.

Matthews said CARTA is looking at adding on-street parking to the system.

Dwyer said the only part of the new parking initiative he doesn't like is the transaction fee.

"I've got a problem with that," he said, adding it ought to be a free service.

Last year several groups including CARTA, the River City Co., the city and others teamed to look at easing the central city's parking predicament.

Downtown workers, residents and visitors faced a shortage of parking spaces at key times and locations, such as on the waterfront.

Officials have implemented a few actions, such as offering discounted monthly parking prices at some lots and garages to hospitality, restaurant and retail employees who may now be feeding meters during the work day.