How to Downgrade IPhone to IOS 11
For most iPhone users, the upgrade to iOS 12 should go smoothly with faster speeds and exciting new features for everyone. And while we haven’t had any issues with iOS 12 on our devices here at Lifehacker yet, we’ve seen a number of reports from other people, especially older devices, who believe they have battery problems after updating to the latest version of Apple. … iOS.
If you’re having problems with iOS 12 and it’s enough to get you back to iOS 11 security, you have a little time to downgrade your device before Apple stops signing iOS 11. (Once that happens, you’re stuck from 12.)
To get started, visit ipsw.me and find your device. You will quickly be able to see if any IPSW files are available – iOS Firmware – for iOS 11.4.1:
If you’re lucky, you should be able to download the iOS 11.4.1 IPSW file to your desktop or laptop. Then connect your iPhone, select it in iTunes and hold down the Shift or Option key and click the Restore button. Find your downloaded IPSW file, get ready to say goodbye to all your data and apps (that is, anything you haven’t synced to iCloud), and start recovery.
Remember that since you’ve upgraded to iOS 12, you will not be able to “restore” your iPhone from a backup that was made in iOS 12. You will have to configure your device from scratch, which means that it is necessary to set the configuration bit … to make your iPhone look and work like it did before iOS 12. If you backed up your iOS 11 device before upgrading to iOS 12, you’re gold status.
How to Uninstall iOS 12 and Return to iOS 11 | Macworld