Focusing on a single metric

Fortunately, the ecosystem provides an early warning mechanism of success (i.e., adoption)...by creating a large enough ecosystem, we can not only encourage a rapid rate of innovation but also leverage that ecosystem to identify success and then either copy (a weak ecosystem approach) or acquire (a strong ecosystem approach) that activity. This is

Each group of users is a cohort — participants in an experiment across their lifecycle. You can compare cohorts against one another to see if, on the whole, key metrics are getting better over time.

Guts matter; you’ve just got to test them. Instincts are experiments. Data is proof.

Mobile businesses are a lot like SaaS businesses: both try to engage users, extract money from them repeatedly, and reduce churn.

Second, make early assumptions and set targets for what you think success looks like,

But there’s good reason to think that the future of applications isn’t mobility — it’s notification.

Optimization is all about finding the lowest or highest values of a particular function.

with interviewees, and letting them tell you what problems they have. You’re not suggesting problems and asking them to rank them.