Wednesday's release of iOS 8.0.1 was unfortunately not Apple's best work. Many iPhone 6 and iPhone 6 Plus users who downloaded the update quickly discovered that their cellular connection was no longer active and that Touch ID stopped working altogether. Responding semi-quickly, Apple pulled the update entirely just a few hours later and said it was actively investigating the matter.
Early on Thursday, Apple posted a support document for affected users outlining a list of steps to safely restore devices back to iOS 8. The support document further states that a fix will be on the way in just "a few days" with the release of iOS 8.0.2.
Apple's instructions to revert back to iOS 8 read as follows:
1. Make sure that you're using the latest version of iTunes.
2. Connect your iPhone to iTunes.
3. Back up your iPhone in iTunes on your Mac or PC. iCloud backups won't restore to earlier versions, including iOS 8.0.
4. Download the file below that corresponds to your device:
- Mac: Press the Option key and click Check for Update.
- Windows: Press the Shift key and click Check for Update.