Daily retention is defined as the number of active devices on day X / active devices during the entire retention period.
Active devices on day X: The number of unique devices with at least one session on day "X" during the selected retention period.
Active devices during the entire retention period: The total number of active devices where the user has at least one session throughout the entire retention period.
Retention = number of active devices on day X / total active devices during the entire retention period
For example, if an app was first downloaded 120 users on May 1st and after 90 days, 100 of those users opened an app at least once, their 100 devices become 100 active devices (The leftover 20 are taken out).
If 30 of these user’s active devices log a session with the on May 8th (7 days after the initial download) then the retention will be 30% on day 7.
Note: Day 0 = May 1st, Day 1 = May 2nd, Day 2 = May 4rd, Day 3 = May 4th, Day 7 = May 8th and so on.
Please reach out to firstname.lastname@example.org with any questions. We hope you enjoy using the Sensor Tower platform!