iOS 26.4.1 is now available to fix a critical iCloud data sync bug that had been plaguing iPhones and iPads running iOS 26.4.0. The issue prevented cloud changes from being delivered to devices, disrupting sync for apps relying on Apple's CloudKit framework, including Apple's own Apple Passwords app. Affected users reported that updates made on one device simply didn't appear on others, leaving shared data like passwords and notes out of sync. Apple acknowledged the regression in its just-released update, which is also rolling out to iPadOS 26.4.0 users.

The fix addresses a problem that had forced developers to submit bug reports while users waited for Apple to address the issue. If you're experiencing sync problems with iCloud-dependent apps, updating to iOS 26.4.1 via Settings should resolve the issue. The problem didn't affect macOS Tahoe 26.4, but iPadOS and iOS users must update to the new version to restore full functionality.