Ian Logan was one of the first employees at Airbnb, eventually becoming the company's Director of Engineering. Now, he's taking the lessons he learned there to build a new start-up called Drop. 

Ian Logan was one of the first employees at Airbnb, eventually becoming the company's Director of Engineering. Now, he's taking the lessons he learned there to build a new start-up called Drop. 

Drop is an app that rewards users with money to spend at their favorite retailers. Logan says it operates as a platform that connects partners and customers. 

Drop just announced a $21 million Series A round of funding. Logan says he plans to use some of that money to triple the company's engineering staff this year. 