Recently, like millions of people, I used a ride-sharing app on my smartphone. It was pretty uneventful and not something I gave much thought. Ride-sharing is simple and convenient, and it’s now an $80+ billion industry. But it wasn’t that long ago that it didn’t even exist. We had cars, we had riders, and we had drivers; but to work, ride-sharing needed smartphones. When they arrived, so did an enormous variety of conveniences and new experiences — some that became entire industries — that we never could have imagined.