Uber and Lyft describe some of their services as ride-sharing, even though there's not a lot of sharing going on. That regular person giving you a ride isn't so much a friend taking donations as a driver who accepts payment. Carpooling app Carma is trying to reclaim ride-sharing, but it needs some help to convince people that real ride-sharing--not just on-demand rides--is actually cool.

So Carma is offering $1 million prizes to regular folks and its own employees for coming up with an innovative way to get people to carpool. The company is opening up its API so developers can take a crack at building an app that boosts shared rides to 10,000 a day for a week straight. Carma employees can win a prize for developing a new feature that attracts 1,000 daily trips in a single city. Carma is only focusing on the Bay Area and Austin in the U.S., but also has a presence in Bergen, Norway, and Kinsale, Ireland.

Carma CEO Sean O'Sullivan said his app, available on iOS and Android, solves a different problem than services like Uber, Lyft, and Sidecar. Carma focuses on reducing the number of cars on the road during rush hour. The app connects drivers heading to work with commuters on their way to the same area, or thereabouts.

"The number of people that take a taxi in a day is about one-fiftieth of people who carpool every day," O'Sullivan said. "Even the people who take taxis aren't using it for commuting to work. There are completely different markets for carpooling and taxi services."

Carpooling reduces congestion and carbon emissions, but getting tens of thousands of commuters to use an app like Carma is a much harder prospect than convincing people that cabs suck. (Which turned out to be easy enough for on-demand ride apps.) While Uber, Lyft, and Sidecar have run into legal issues in basically every city they enter, Carma flies beneath the radar. Because passengers simply reimburse drivers for the cost of gas and maintenance, transportation officials don't consider the app competition for cab companies or level the same scrutiny on Carma's operations.

O'Sullivan said he's in talks with car manufacturers to integrate Carma into connected car products. He's hoping developers will bundle the app into their own products, like mapping and transit apps or community-oriented services.

Carma is also opening up a $500,000 accelerator program this fall to entrepreneurs who want to work out of the company's Irish headquarters for a few months. That program is currently accepting applications.