Apple: phased release for automatic updates
In App Store Connect you can release an update over 7 days: 1%, 2%, 5%, 10%, 20%, 50%, then 100% of users with automatic updates turned on. Anyone can still update manually from the App Store. You can pause the rollout (for up to 30 days in total) or release to everyone right away.
Google Play: staged rollout
In the Google Play Console you choose the percentage yourself (e.g. 5%, 20%, 50%) and increase it when you're confident. You can halt a staged rollout if something goes wrong.
What to watch during a rollout
- Crash rate and Android vitals.
- New app reviews — users report problems in reviews within hours, often with details your crash tool doesn't have.
- Key metrics such as sign-ups or purchases.
Getting new reviews in Slack or Teams with app review monitoring makes a rollout much easier to judge.
Example
On day two of a phased release, three one-star reviews mention that the app logs users out. The team pauses the release at 2%, ships a fix, and avoids a ratings drop for the other 98%.