In this issue:Building for Power Users—Some apps are used very intermittently for a one-off purpose, like ordering food or checking on the status of a financial transfer. Some are used all the time, but as a cure for boredom and a substitute for not knowing what to do. And then there are apps for power users, where the typical user is constantly engaged with the product and uses it not just as a tool for working but as a tool of thought. These are an important category, where many of the rules o...