Albert Koehl is an adjunct professor of natural resources law at Osgoode Hall Law School, the author of the online guide Road Follies, and a founder of Bells on Bloor.

I was so excited to hear about the new Rover parking app that I immediately signed up even though I don’t have a car, or a parking spot … or even a working mobile phone. The reason for my excitement? The parking app unlocks huge amounts of underutilized or unused space in urban areas. It’s as if we magically discovered a new land in the middle of the city.

The app, introduced by two Toronto entrepreneurs (and based on existing models in the United States and Europe), connects the owner of a private parking spot with a motorist looking for one. When a motorist needs parking, a quick consultation with the app directs him or her to an available spot. The space can be booked for as little as 30 minutes at a cost of up to $2 an hour, billed to the motorist’s credit card. The app counts down the time remaining, which can be easily extended without compromising a shopping trip, spa treatment or cup of coffee with a friend.

The app helps to convert unused private space to a productive function. It also provides new income for the owner of the spot. Perhaps most important, the city gets the opportunity to liberate an equivalent amount of parking on public road space for other community priorities, such as wider sidewalks, safe cycling conditions or green spaces.

On my downtown block, which sits adjacent to a busy retail area along Toronto’s Bloor Street (the scene of a decades-long fight for bike lanes), there are 35 front-yard parking spaces plus 15 driveways, some leading to backyard parking. Many residents head out by car in the morning, leaving behind empty parking spots. If even a small fraction of these homeowners make their parking space available for the app, parking capacity in the immediate area increases substantially.

The income opportunity need not be restricted to homeowners, but could benefit schools, churches and other institutions whose activities are limited to specific hours or even days of the week. A vacant school parking lot suddenly becomes a (windfall) revenue source to fund nutrition programs or extracurricular activities.

A knock against the new app is that its convenience might encourage more driving, and therefore increase local traffic. This claim has the facts backward. I would rather see a motorist on my street with a precise destination than one who circles the block looking for parking. It’s the search for parking, particularly for curbside parking spots that are provided for free – as is the daytime norm on side streets – that brings more traffic.

In The High Cost of Free Parking, Donald Shoup, an urban planning professor at the University of California, Los Angeles, studied the extra distance travelled by motorists to find a free parking spot in a 15-block area of L.A. His finding: an aggregate of 1.5 million kilometres of extra driving in a single year (enough to travel to the moon and back, twice).

The biggest challenge for the Rover entrepreneurs is that their competition – that is, the City of Toronto – gives a lot of curbside parking away for free (or, to be accurate, subsidizes parking by forgoing revenue).

When motorists pay a market rate for parking (as with the parking app) and bear the true cost of driving, they are more likely to choose other options for getting downtown, such as car pooling, cycling or transit. Residents worried about excess motor traffic would do better to ask cash-strapped city hall to explain its free-parking approach for side streets.

City of Toronto officials have suggested that the commercial use of a private parking space contravenes municipal bylaws. Mayor John Tory is right to say he is willing to review these bylaws to bring them up to date with new technologies. After all, it’s not every day that new land is discovered in downtown Toronto.