Retention (app)

The share of installs that keep using the app after a defined period, e.g. day 7.

Report it by acquisition source. Channels that look cheap on cost per install often look expensive once day-7 retention is attached.

Early retention is mostly an onboarding problem, not an acquisition one — which means the fix usually sits with product.

It is the metric that separates growth from churn dressed up as growth.