For jailbreakers, you are still getting chance to downgrade back to them to lower version.
Here’s how to downgrade iOS 11.4 to iOS 11.3.1 or below on your iPhone/iPad using iTunes via IPSW file without losing any data.
Note: If you are on a lower version of iOS 11.2, 11.2.6, or 11.3 do not upgrade it to iOS 11.4 as you are on the right path for iOS 11.2-11.3.1 jailbreak. No matter if you have already installed iOS 11.4, then you can still downgrade it to a lower version to iOS 11.3.1.
Reason to Downgrade from iOS 11.4 to iOS 11.3.1
There may be a lot of reason for updating your iPhone to iOS 11.4 either accidentally or not satisfying. So if you are a fan of jailbreak it’s never too late to downgrade it. You can easily downgrade your iPhone right now from iOS 11.4 to iOS 11.3.1 and wait for a jailbreak release.
How to downgrade iOS 11.4 to iOS 11.3.1
Since Apple is still signing the iOS 11.3.1, and downgrading to lower version is possible. So, follow this guide to downgrade to iOS 11.3.1 on iPhone/iPad right now before Apple stops the iOS 11.3.1.
First of all, you need to download the iOS 11.3.1 firmware file for your device from ipsw.me.
Step 1# Upgrade or download iTunes to the latest version on your Mac or PC.
Step 2# Now Turn off Find my iPhone & disable passcode lock via the Settings app. (Settings > Account Icon > iCloud > Find my iPhone).
Step 3# Launch iTunes & connect your iPhone, iPad & iPod Touch using a Lightning USB cable to your computer.
Step 4# Hold the Alt/Option key on the Mac or Shift Key in Windows on your keyboard and click Update or Restore.
Note: IF YOU WANT TO FRESH INSTALL THEN GO WITH RESTORE OTHERWISE UPDATE IT.
Step 5# Now Select the signed ipsw iOS 11.3.1 file you had downloaded earlier
Step 6# Then click on the Restore iPhone.
Step 7# iTunes will inform that it will restore your iPhone to iOS 11.3.1 and Click Restore
After restored, your device will reboot to the welcome screen and will now install iOS 11.3.1 on your device.
That’s it. Your device should now be successfully downgraded to iOS 11.3.1 from iOS 11.4. Your downgrading process is completed; you need to now set up your device by following the on-screen instructions.
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