Customers have a wide array of options in today's marketplace, and users are likely to abandon your product unless you take proactive steps to understand their needs. At the same time, your continued success depends on loyal, revenue-generating customers. Both of these groups can be tracked using engagement metrics.

Your segments become especially powerful when they incorporate engagement metrics. Segments that use engagement metrics typically focus on a customer's lifetime in your app, their retention in the app, and their purchasing behavior. In our All Things Sports app, we might create the following engagement-based segments:

• Customers who signed up in the past week
• Customers with multiple sessions per day
• Customers who have logged in and made a purchase within the past month

In order to be effective, these segments must be dynamic. In other words, if you look at any of the segments listed above one week, and then look at the same segment the following week, the list of customers who belong to those segments should be different. You can calculate these segments yourself, but it is far more effective to use a third-party tool to automatically refresh the list of customers based on the definition of the segment.