The company said its zero-emission drones have now flown more than 70 million autonomous commercial miles across four continents. : Autonomous delivery drone startup Zipline said Friday that it hit its 1 millionth delivery to customers and that it's eyeing restaurant partnerships in its next phase of growth. The San Francisco-based startup designs, builds and operates autonomous delivery drones, working with clients that range from more than 4,700 hospitals including the Cleveland Clinic to major brands such as Walmart and GNC.