Prefer, which is being unveiled on Monday, is a mobile app that lets you get recommendations for services like massages, babysitting, and hair styling from contacts on your phone. The goal is to give users access to reviews from people they trust rather than from the strangers on services like Yelp or Zeel, an app that, like Prefer, can also be used to book and pay for appointments.

“It’s a simple question: Would you rather have a massage therapist your friend recommends or someone random on Zeel?” Belsky said in an interview with Fortune.

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Prefer faces major challenges in getting traction. In addition to Yelp (“YELP”), Thumbtack, and Angie’s List, it faces competition from Zeel and fellow niche app StyleSeat, for booking hair and beauty appointments. Thumbtack also lets users book services like personal training while Amazon (“AMZN”) has a service for booking handymen and other professionals. And, of course, people regularly use Facebook to ask friends for recommendations.

Belsky, whose previous startup, Behance, was acquired by Adobe, believes that the advantage of social recommendations will win out, however. His company hopes to make money by charging a small fee for every transaction through its app.

In early testing in New York, people used Prefer to book bartenders and tailors.

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Belsky said he and his co-founder, former Facebook employee Julio Vasconcellos, have raised an undisclosed amount of funding from early Uber and Twitter investor Benchmark, where Belsky is also a venture partner.

Prefer’s app works by scouring users’ phone books to detect whether any of the contacts include service professionals. The app then asks users whether they would recommend those people to friends.

Users can also see reviews of professionals that their friends have submitted and who also use Prefer.