General Motors has expanded its car-sharing service Maven to Chicago and will add Boston and Washington D.C. to its lineup this summer as it ramps up the five-month-old business.

Maven, which launched in January, is more like three car-sharing services in one, breaking down to a city-based service called Maven City that rents GM vehicles by the hour through an app, another for urban apartment dwellers, and a peer-to-peer sharing service that started in Germany.

“We’re super excited to get to a big stage now,” Julia Steyn, GM’s head of urban mobility told Fortune. “This is what we’ve been working towards. Maven being in Chicago, Boston, and DC opens up the user experience in a much more relevant way.”

Users can download the Maven app to search for and reserve a vehicle, unlock the door, and remotely start, cool, or heat the car. Every GM vehicle is equipped with Apple CarPlay and Android Auto, a software platform that lets users to integrate their smartphone and with a vehicle’s dashboard. The cars in the Maven service also have GM’s in-car communication system OnStar, SiriusXM radio, and 4G LTE wireless.

The automaker, which has announced several initiatives this year that highlight its interest in unconventional transportation, waded tentatively into the city-based service, initially launching with only 21 vehicles in Ann Arbor, Mich. The program, while open to everyone in the city, targeted faculty and students at the University of Michigan. Meanwhile, the residential on-demand car sharing dubbed Maven+ was only available to apartment dwellers living in Stonehenge Partners properties in New York.

Maven City is now operational in Chicago with pricing starting at $8 an hour, including insurance and fuel. Registered customers use the Maven app to reserve one of 30 vehicles at more than 15 sites throughout the city. Maven is also expanding its residential program to Chicago to residents of the Aqua luxury high-rise apartment community in the city’s Lakeshore East neighborhood.

Maven has partnered with Zirx, a mobility services platform startup, to provide an on-demand delivery option in Chicago that will let users order a car. If the delivery option proves successful in Chicago, which Steyn anticipates, it will be expanded to other cities, she said.

Next month, Maven+ will be available to residents of the Hepburn, a 195-unit luxury apartment community in Washington D.C.’s historic Kalorama neighborhood. Maven City will open to all qualifying D.C. residents by the end of June. Boston will follow later this summer, GM says.

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Car-sharing was once the dominion of startup companies like Getaround, Turo, Silvercar, and Zipcar vying for customers. Now, a growing group of automakers that are looking for new ways to earn money beyond their traditional businesses of making, selling, financing, and servicing cars have jumped in. Audi, BMW, Ford, and Daimler are either testing out car-sharing or operating commercial services. Daimler’s Car2go is one of the largest. BMW just relaunched its car-sharing service in Seattle under a new name and different technology platform after failing in San Francisco.

GM is taking an all of the above approach to car-sharing. For instance, Maven recently launched a peer-to-peer car-sharing pilot in Warren, Mich. as well as a campus car sharing service at GM do Brasil headquarters in Sao Cataeno do Sul, Brazil. GM is also using its own campus car-sharing locations as beta labs for testing future shared mobility services.

Ride-hailing company Lyft, which partnered with GM in January, is now using the Maven platform for the Chicago Express Drive short-term rental program that kicked off two months ago. Express Drive allows Lyft ride-sharing service drivers in the Chicago area to rent Chevrolet Equinox crossovers for $99 a week. Chicago Express Drive has grown to more than 200 cars in eight weeks. As previously announced, Express Drive will expand to additional markets including Boston, Baltimore, and D.C. by the end of the year.

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It’s difficult to measure the success of Maven because its initial launch city was a smaller university town and the residential programs are narrow by design. The company says in the past three months, the number of users has doubled to 1,500. But that’s tiny compared to more established car-sharing services like the Daimler-owned Car2go, which has 78,000 registered users and 750 two-seater Smart Fortwo vehicles in Seattle alone.

The real test will begin once it’s established in bigger metro areas later this summer. Maven has a chance to gain some market share. The pricing is competitive, and users will have a number of cars to pick from, including the Chevrolet Volt plug-in electric hybrid, unlike other services that offer one car model. Early data shows a broad mix of users—for instance, only 30% in Ann Arbor are millennials—which is a positive sign, Steyn says.

And the company has big ambitions. More than 50 people now work for Maven, a 25% increase since launching, and it has plans to rollout to other cities.

“We have very ambitious goals,” Steyn says. “We are not going to just stay with these three cities and our ambitions are not just to rollout Maven services in the U.S.; we’re doing it globally.”