Generally, the retention metric refers to customers, who regularly return to the shop or use the product. In UX, higher retention points on good usability.
It is calculated the following way:
Retention N = number of visitors in a particular day/number of users, installed the app N days ago * 100%
Meanwhile, there are four various kinds of retention, that shall be accounted here:
- Rolling retention
The most popular way to measure retention. It shows the volume of users coming back in an N-day from the moment of installation or later.
- Full retention
The metric refers to some visitors, coming back to the app every day till N-day. So, full retention of the 10th day is a percentage of users, who were returning to the app from the first to the 10th day.
- Return retention
Gives a percentage of users, who came back to the app at least once during N-days. As an example, Return retention of 25th day will account for each visitor, used the app any day from the first to 25th.
- Bracket-dependent return retention
It resembles return retention, fixing the number of users who came back to the app at least once in a chosen period. For instance, bracket-dependent return retention from the 15th to 21st days will give the volume of users, opened the app during this period from the time of the installation.