Too Long; Didn't Read
Developers, teams, and businesses of all sizes use Heroku to deploy, manage, and scale apps. To understand how your app is performing in production, you need to measure the right things. There are three broad types of app metrics that you should be tracking: engagement, retention, business, and performance. Four numbers in particular are must-haves: daily active users (DAU) monthly, monthly MAU and monthly session length. Average session length is essential to interpreting average session length and how users are using your app.