A session interval is defined as the amount of time between two consecutive app sessions. This, like other metrics, is quite important while calculating user engagement or retention over a specific time period.
To be more precise, it gives you a clear picture of how ‘sticky’ your mobile app is in a user’s perspective. High engaging apps will have shorter session intervals, as this would indicate that a user is returning to your mobile app quite frequently. On the other hand, less engaging apps will have longer session intervals. However, it is also important to note that this number will also depend on the industry or sector that your app falls in. For example, banking and finance apps will have very different session intervals as compared to messaging or social media apps.