Historically, new models of computing have tended to emerge every 10–15 years: mainframes in the 60s, PCs in the late 70s, the internet in the early 90s, and smartphones in the late 2000s. Each computing model enabled new classes of applications that built on the unique strengths of the platform. For example, smartphones were the first truly personal computers with built-in sensors like GPS and high-resolution cameras. Applications like Instagram, Snapchat, and Uber/Lyft took advantage of these unique capabilities and are now used by billions of people.