User segmentation is the practice of dividing your app users on the basis of past or real-time behavior, specific actions (and/or inactions), over a period of time.
Segmentation is necessary the larger your user base becomes. It becomes easier to subdivide a huge market into smaller groupings (or segments) of users with similar needs and wants.
There are very few companies who have the capability to answer the needs of every single customer it acquires. Rather, companies have to use segmentation to identify their ideal segment so they can focus their marketing spend on the users most likely to convert.
Segmentation can be accomplished in various ways. But the typical strategies involve grouping users by: