What should a taxi look like? Maybe it should be painted solid red, like a D.C. Taxicab Commission panel suggested in February. Maybe it should have a standardized dome light on top and a credit-card reader inside. The commission is requiring that all taxis have both gadgets in the next few months.

Or maybe it should resemble the black Dodge Charger that picked me up in Chevy Chase, Md., last Friday night. There were no lights on the roof — just blue interior ones that gave the backseat a cool glow. And up front, there was no taxi driver. Instead, it was Abiy, an engineer who loves to drive and is earning extra cash for his upcoming wedding by spending his weekends using SideCar.

SideCar, which launched in D.C. last month, is the newest smartphone app in town to summon rides on demand. But unlike Uber, which connects folks with professional sedan drivers, and the slew of competitors — including UberTaxi, Taxi Magic and MyTaxi — that virtually hail traditional taxis, SideCar doesn’t require the person behind the wheel to be on the job.

Anyone with a car can apply to be a driver in SideCar’s network. Once they pass a background check and get training, they can connect with passengers who’ve requested a pickup. And rather than have a set rate, SideCar spits out a suggested donation, which users are allowed to deviate from as much as they want when they settle their bill via cellphone. (That’s the trick that has allowed SideCar, so far, to escape taxicab regulation.)

Even in D.C., with its history of slugging — a low-tech version of SideCar that helps people take advantage of HOV lanes — most people I’ve discussed SideCar with think it’s nuts. But I don’t buy the argument that it’s any more dangerous than getting into a cab. Before Abiy arrived, I saw his photo and a picture of the car, so I knew exactly whom to look for. The whole trip was tracked by GPS. And he had every incentive to offer a comfortable, direct, safe ride.

I gave him a five-star rating and the suggested donation, which was exactly what a friend recently spent for the same trip in a traditional taxi.

Abiy gave me a lift home, a bottle of water and something to think about: What if all cars were signed up for SideCar?

For now, the service is essentially a pay-what-you-want taxi. Abiy wasn’t planning to drive across town until he picked me up.

But if a driver coming down the street happened to be going my way, and we were able to communicate that with each other, I could pay less money and we’d both benefit. If we could make those kinds of trips happen on a larger scale, we’d reduce congestion on roads and everybody would arrive at their destination faster.

We’d still need traditional taxis to ferry passengers to places no one else is headed. But whether they’re red or not, we’d start looking at them in a very different way.

SideCar Sign-Ups

Interested in signing up to be a SideCar driver? If you have a four-door car that’s in “great condition” (year 2000 or later), valid insurance, a current driver’s license and a clean background, you’re a good candidate. Submit your name and contact info at Drive.side.cr to get the process started. For folks who want to get a ride, download the app (available for iPhone and Android), enter your credit-card number and pinpoint where you want to get picked up and where you’re headed. Rides are currently available on Friday and Saturday nights.