When someone buys a new smartphone, often they’re preoccupied with the camera specs or the size of the screen or its storage capabilities. It’s easy to overlook one of the most foundational aspects of these sleek consumer gadgets: their operating systems. The world’s most popular mobile operating system is Google’s Android. It powers more than 86 percent of smartphones in the world. What’s even more remarkable is that Android is based on the open source Linux operating system.