What is app retention rate (D1, D7, D30)?

Retention rate is the share of users who come back to an app a given number of days after installing it — on day 1, day 7 and day 30 are the usual checkpoints.

Most apps lose the majority of new users in the first days, so D1 retention says whether the first session worked and D30 whether the app became a habit.

Retention is for all users; churn is for paying subscribers. An app needs both: people who come back, and payers who stay.