Can I remove iOS 9.3 from my iPad and iPhone, and reinstall iOS 9.2.1?

Update, 22 March 2016: Apple has released iOS 9.3 to the public after months of private and public beta testing. Apple is still signing iOS 9.2.1 meaning a downgrade is possible, although this option will only be available for a few days and caution should be taken. 

How to downgrade from iOS 9 to iOS 8

The final version of iOS 9.3 is now available to owners of all compatible iPhone and iPad models. We explain how to install iOS 9 here: How to update to iOS 9 on iPad or iPhone.

The beta version of iOS 9.3 has been available for some time, but now the full version has launched. Before jumping in and installing the new version, some people will be keen to know whether it will be possible to revert back to iOS 9.2.1 should the worse happen and apps you rely on not work, or you find your iPhone starts to slow down or become unresponsive (which sometimes happens with older models - although Apple says iOS 9 is compatible with all the same iPhones, iPads and iPod touch models that were able to run iOS 8).

While some might suggest biding your time before updating to iOS 9.3 to see if any errors are reported, if you are keen to try iOS 9.3 (or had been running the beta of iOS 9.3 that has been available since earlier this year) then you'll want to know two things: what steps to take to safeguard your data and settings before updating to iOS 9.3, and how to go back to iOS 9.2.1 if you need to. We cover these questions in this article.

We look at preparing for the install first, for obvious reasons, but if you're already running the iOS 9.3 and want to go back, you can jump straight to our section on downgrading from iOS 9.3 to iOS 9.2.1.

For more general advice on iOS updates, as well as explanations of how to update to the official version of iOS 9, see Complete guide: How to update iOS on iPhone or iPad.

Read next: iOS 9 review | iOS 9 tips | iOS 8 vs iOS 9 comparison review

Before we start talking about how to downgrade from iOS 9.3, however, here's a video of our favourite new features in iOS 9:

Also read: How to use Apple's Notes app in iOS 9 | How to get the Apple News app in iOS 9 | How to use Proactive in iOS 9 | How to search in iOS 9 | How to use public-transport directions in iOS 9 Apple Maps

What to do before you update to iOS 9.3

As with any iOS update, you should be careful to back up all your data and settings before installing the new software.

But Apple advises still more caution than this (at least for those installing the beta, but it's still worth being this cautious with the full version), warning that you should back up to iTunes specifically (rather than to iCloud) and then archive the backup.

"If you back up to iCloud or if you don't archive your backup, you won't be able to restore from it if you go back to current version of iOS," Apple points out. It even advises you to make sure you're running the latest version of iTunes.

Here's how to archive an iTunes backup and prepare for iOS 9.3:

  1. Plug in your iPad or iPhone and start up iTunes on your Mac. 
  2. Click Summary, then Back Up Now.
  3. Wait for the backup to finish.
  4. Now select iTunes > Preferences > Devices and look for your device’s backup.
  5. Hold the Ctrl key and click on the backup. Finally, select the option Archive.

This creates a safe backup that we can return to after trying out iOS 9.3. Next we'll look at how to go back to iOS 9.2.1 (and restore the backup we just created) from iOS 9.3.

Read next: How to use public-transport directions in iOS 9 Maps

How to downgrade from iOS 9.3 and reinstall iOS 9.2.1 - the complete guide

Removing iOS 9.3 (or any other version of iOS) and downgrading to the previous version is relatively straightforward, provided you do so within a few days of launch. There's a brief window (generally just a few days) after Apple releases a new full version of iOS, during which the company continues to 'sign' (or authorise) the previous version. In those few days you can downgrade reasonably easily. Follow these steps to remove iOS 9.3 and go back to iOS 9.2.1:

1) Back up. Really! Back up now. During the reinstallation process, iOS will wipe all of the apps and data from your iPhone or iPad (except for the undeletable, stock apps). Make a backup of the device before you begin the following procedure.

It’s worth noting that you won’t be able to restore this backup to your iPhone as iOS 9.2.1 isn’t compatible with iOS 9.3 backups, and we’ll be using the archived backup we took above instead. If you haven’t archived an iOS 9.2.1 (or earlier) backup, we would advise backing up iOS 9 to iCloud to avoid overwriting the standard backup on your Mac.

2) Get an .ipsw file for the previous version of iOS 9.2.1. To reinstall iOS 9.2.1, you need to acquire the iOS 9.2.1 IPSW file. If it's stored on your hard drive you can find it by following the path youruserfolder/Library/iTunes/ and then within a folder called iPad Software Updates, iPhone Software Updates or iPad Software Updates.

If you can't find the latest one on your Mac - which is fairly likely, giving the Mac's tendency to delete them periodically - then don't worry. Simply run a search for download ipsw and select and download the appropriate file for your device. There are plenty of sites to choose from.

3A) Open the .ipsw file. Assuming that Apple is still signing iOS 9.2.1 (it's likely to stop a short time after iOS 9 launches), the following steps should be fairly easy. Plug your iPhone or iPad into your Mac (or PC - the steps are essentially the same), then launch iTunes. Click on your device in the iTunes interface and select Summary. Now hold down the Alt/Option (or Shift on a PC) key, and click the Restore button. (You'll need to disable the Find My feature on the device if you've enabled it.)

Now navigate to the iOS 9.2.1 ipsw file and click Open. iTunes will now reinstall iOS 9.2.1 on your iPad or iPhone.

3B) If necessary, go into Recovery mode. If iTunes says you're already running the latest version of iOS on your device, you may need to use Recovery mode. Shut down the device, plug one end of the syncing cable into your computer and hold down the Home button on the iPhone/iPad while you connect the cable to it. When the Connect to iTunes screen appears, release the Home button.

iTunes will say that your device is now in Recovery mode. Hold down the Option key (Alt), click Restore, navigate to the iOS 9.2.1.ipsw file, and install it on your device.

Read next: How to change an iPhone or iPad passcode from 6 digits back to 4 digits in iOS 9

Downgrade from iOS 9.3 to iOS 9.2.1: How to tell if Apple has stopped signing iOS 9.2.1

At some point in the next few days, Apple is going to stop signing iOS 9.2.1, and this procedure will get a lot more complicated.

If you get an alert that says this version of iOS is not compatible with your device, that means Apple has closed the window. You're probably stuck with iOS 9.3, but we'll look into any remaining methods of downgrading when we next update this article.

Good luck!

Read page 2 for the advice we gave to beta testers before iOS 8 launched to the public. Some of this advice is now out of date...