Parking on Toronto streets is getting easier thanks to the parking authority’s smartphone app.

The free Toronto Parking Authority app, unveiled in March 2015 for use paying for parking in Green P lots, is being activated for on-street parking across the city between now and the end of the year.

On-street spots that are app-enabled will have a four-digit location code that will be visible on pay-and-display machines and hours-of-operation signs. Users punch in the location code, time they want to buy and automatically pay by credit card, just as they currently do with the three-digit location codes in ungated Green P lots.

App users get warnings before their time expires, and can add time to the meter remotely, without returning to their cars, if they are away longer than expected.

The service is starting downtown on Elm St., west off Yonge St. Motorists will still be able to pay with cash or credit card if they prefer.

Mayor John Tory, who arrived on Elm by car and paid for parking using the app in front of TV news cameras, said Toronto, has fallen behind other big cities in harnessing technology.

“The Green P app is an example of how we can modernize the services the city offers and the way the city delivers them,” Tory said, vowing that Torontonians will see other innovations rolling out in months and years ahead.

Parking enforcement officers use hand-held, network-connected terminals that tell them if a car is paid up.

The parking authority expects that expanding the app to on-street parking will boost the number of users. About one-quarter of payments are not made through smartphones.

The app has been downloaded about 250,000 times and used about 1.5 million times.