Every 0.1% of crash rate compounds into churn.
A crash-free rate of 97.8% sounds fine until you do the maths: across a daily-active user base of 50,000, that is roughly 1,100 users hitting a crash every day. The Apple App Store and Google Play algorithms downrank apps with elevated crash rates. Reviews tank. Customers who experience a crash on first launch never come back. The difference between 97.8% and 99.7% is not technical — it is the difference between a mobile app that retains customers and one that bleeds them quietly every week.