Compass

Founded by Ori Allon—the former Director of Engineering for Twitter—and Robert Reffkin—formerly the Chief of Staff to the President and COO of Goldman Sachs—Compass is the first residential brokerage in the country to offer a proprietary mobile app exclusively for its agents, enabling them to update listings, conduct searches, respond to leads and communicate with clients. The agent app, in addition to the company’s integrated consumer web and mobile platform, was built by a team of 17 staff engineers who hail from companies including Google, Twitter and Facebook.