Apple Releases 8.0.1, But Don’t Update Yet
A number of iPhone users are reporting that the update breaks cellular connectivity and Touch ID.
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If you’ve already installed the update and are experiencing these issues, your only recourse until Apple releases a corrective update is to restore your device back to iOS 8.0. iMore has instructions on how to do that.
Apple has pulled the 8.0.1 update. An un-updated iPhone 6 Plus is now reporting that iOS 8.0 is up to date.