Phased release is Apple's built-in slower rollout for iOS updates. It gives you time to watch crashes, reviews, support tickets, and server load before the update reaches everyone with automatic updates.
How it works
Apple says a phased release for automatic updates rolls a version out over a seven-day period to a percentage of users who have automatic updates turned on.
When to use it
- Large migrations or account changes.
- Major UI changes that might trigger support volume.
- Backend-dependent releases where traffic shape matters.
When not to use it
If the release fixes a severe issue that affects most users, a slow rollout may be the wrong tradeoff. Use phased release when monitoring risk is more important than instant coverage.
Source notes
Apple's platform version information reference describes phased release as a seven-day rollout for users with automatic updates on.