App-based taxi hailing services are not new to Kenyans. But a little-known local app called Maramoja hopes to challenge the established players by tapping social networks and catering to local practices, primarily Kenyans' penchant for using familiar, trusted drivers.

Uber and Easy Taxi, a ride-hailing service that has grown internationally by focusing on developing markets, have already established services in Kenya.

Maramoja, however, is offering another take on the taxi-hailing business.

"We are built on trust," said Jason Eisen, the founder and CEO of Maramoja. "All of our competition see the taxi driver as an anonymous, faceless, nameless function, not a person. They think that a client doesn't care which driver they go with, that they just want the closest driver -- for us, we understand that this is not actually how Nairobians use taxis."

Most people in Kenya have their favorite neighborhood taxi guy who is on call on special occasions such as late night appointments or medical emergencies. Depending on the user's location, he might have multiple taxi drivers he deals with on a regular basis.

This means that there has been a long relationship with the driver, and this is what Uber and Easy Taxi are driving away from, Eisen said.

Eisen explained that once a user downloads Maramoja's application, it searches email and social media contacts for favorite taxi services and drivers. It then matches the service's network of drivers with the driver and taxi contacts in users' applications. If a user's favorite drivers are not on the Maramoja platform, the user can submit them and they will get an invitation to be a Maramoja driver.

Maramoja offers users account credits for free taxi rides for referring clients and drivers. The procedure ensures that users do not lose touch with the driver of their choice, while building out a network of trusted drivers that users can share with social network friends.

The company also does its own background check on every driver they add to their database.

"Any time you are making a ride request to Maramoja we are not only able to connect you to the nearby taxi but to a nearby trusted taxi," Eisen said. "We do not want to come between you and your favorite driver."

Eisen said up to 80 percent of the company's clients are Kenyans, rather than expatriates from outside the continent, underlining their success in adapting to the Nairobi taxi culture.

Maramoja also charges rides by zones rather by time or distance. This means that the fares are fixed-priced, regardless of traffic jams or distance.

The use of cash and mobile money payments has worked well for Maramoja. Recently, Uber launched cash payments in Nairobi to capture more of the market, where credit cards are not used as much as in other countries.

Maramoja has also launched its "boda boda" motorcycle taxi service. Motorcycles are a popular form of transportation in Nairobi and motorcycle taxis are common. This means that Maramoja's trusted taxi service is available at a much lower price tag for users who like to depend on motorcycles for their travel.

Eisen, an American-born entrepreneur, spent a lot of time in Kenya and saw the tremendous growth of technology as way to solve serious problems, including the adoption of mobile money services as a way to serve rural people without bank accounts. In November 2012, he resigned from his job as a consultant with a U.S.-based firm and came to Kenya to start Maramoja, which launched publicly in March 2014, beating the international companies to Kenya.

The big venture capital-backed Uber and Easy Taxi have become formidable forces in the market, however. Uber has the money to offer subsidized rides while Easy Taxi has taken its advertising campaign to overdrive in the Kenyan media.

On its part, Maramoja received funding from a local angel investor last year, but Eisen declined to provide details.

But money is not the only thing needed to succeed, Eisen said. "There is no question that resources can help get your name out, or buy technology to make your service better or more locally relevant; at the end of the day I don't think it's a substitute for a product that fits Nairobi and drives well with the culture we have here."