"In 2011, Tracey Young's company PlanGrid was accepted into the prestigious start-up incubator Y Combinator, and with Young as CEO, it has since been used on 400,000 projects in 195 countries. Its benefits—logistical and economic—are so apparent that one project manager recently told Young that learning about it felt like being taught to use fire for the first time. Top venture firm Sequoia Capital sees the same magic; they've invested $30 million. "I joke that I used to work for one superintendent," Young says. "Now I work for hundreds of thousands." News story from Elle.com