Jeff Tangney

Doctors congregated and networked online before former Epocrates exec Tangney founded Doximity in 2010, but they did so helter-skelter. The first wave of networking sites may have offered many of the features doctors wanted, but they were desktop-first entities—and for practitioners on the go, a more mobile solution was a must. "Lots of doctors don't have desks. They go from exam room to exam room," Tangney says. "Easy access from mobile devices was what would make this work."
Fueled by the mobile-first approach, Doximity quickly became the largest and most admired professional network for physicians—and the one in which physicians feel most protected, owing to the network's stern authentication protocols. "Our motto now is the same as when we started: physicians first," Tangney says. "We've got six full-time physicians on staff. What's best for them drives just about all of our product decisions and development." —Larry Dobrow