A start would be to remind tech companies of one of their core principles: user-centered design. Understanding city life means living city life. Not just commuting to it or from it and certainly not believing you understand a person\’s situation just because you pass him or her on the street from time to time. The best products are those that begin with a user\’s motivation and needs. They are empathetic applications. To crack the nut of urban-scale opportunity — and there is a lot of it, just look at the \”sharing economy\” successes of Uber, Airbnb, and Zipcar — technology must be built amidst the same forces that create the problems it is trying to solve.