Apple released its latest iOS 10.2 with a number of new features, but some users may still want to downgrade to a previous version of iOS.
If the new iOS 10.2 features are not what you want, if the build is buggy on your device or if you have some other reason to drop it, you can downgrade to iOS 10.1.1 or iOS 10.1 for a limited time.
Apple doesn't officially support downgrading iOS updates, but there's a small window of a week or so after an update's release during which users can still downgrade. The option to downgrade to iOS 9 is long gone, but users can still roll back to iOS 10.1.1 or iOS 10.1 for now.
First of all, before rolling back to iOS 10.1.1 or iOS 10.1 you have to make sure you have the latest version of iTunes installed. If you're not sure, just open iTunes and head to Help > Check for Updates. If you're running an older version and an update is available, iTunes will offer instructions on how to get the latest version.
Once that's all set, make sure to back up all of your data via iTunes or iCloud, otherwise you could lose everything for good.
Lastly, before proceeding with the downgrade, disable passcode, Touch ID and Find my iPhone/ iPad.
How To Downgrade From iOS 10.2 To iOS 10.1 Or iOS 10.1.1
To roll back to a previous iOS version, first of all download the iOS 10.1 or iOS 10.1.1 IPSW. Check this list to find your specific device and get the IPSW you need. Once you've downloaded the file, connect your device to a PC, fire up iTunes and select device summary for the connected iDevice.
Next up, hold down the Home and Power buttons simultaneously to get your iPhone or iPad into DFU mode. Release the Power button when the device shows the Apple logo on its screen, then wait for the Connect to iTunes logo to turn up. When iTunes displays a message with Device in Recovery, you can release the Home button as well.
From here on, you'll have a choice to either restore or update. You want to restore, so hold down the Alt key on Mac or the Shift key on a Windows PC while clicking Restore in iTunes. Find the IPSW file you downloaded, select it, follow the on-screen instructions and hit Install.
At this point, all you have to do is wait for iTunes to restore your iPhone or iPad to iOS 10.1 or iOS 10.1.1, depending on the version you've chosen to roll back to. When it's done, the iPhone or iPad will reboot and will show the Hello screen.
If you later decide you do want the latest iOS version after all, here's how to download and install iOS 10.2 on your iPhone, iPad or iPod touch.