How do I downgrade from the iOS 10 developer preview beta and go back to iOS 9? And can I remove iOS 9.3.2 from my iPad and iPhone, and reinstall an earlier version of iOS?

Apple unveiled iOS 10 at WWDC 2016 in June 2016, and it's already available in its developer preview form (for app developers only, in other words) and public beta form (for everybody else) if you want to install it on your iPad or iPhone.

If you've taken the plunge and installed the iOS 10 public beta, and then regretted it, you're probably wondering how to delete iOS 10 and go back to the comforting embrace of iOS 9. This is straightforward, if a little longwinded. Those on iOS 9.3.2, in turn, may wish to downgrade from iOS 9.3.2 to an earlier version of iOS. This is more challenging.

In this article we look at various methods of downgrading from one version of iOS to an earlier one. We'll start by explaining how to remove the iOS 10 public beta and reinstall iOS 9, and then move on to downgrades from iOS 9.3.2 to earlier versions of the OS.

Read next: iOS 10 release date & new features | iOS 10 review | iOS 9 vs iOS 10

How to remove the iOS 10 public beta and go back to iOS 9: Downgrade from iOS 10

Let's deal with the early birds first - the ones who have installed iOS early, be it via the public beta or developer preview.

How to remove iOS 10 and go back to iOS 9

You're the lucky ones when it comes to downgrading, because iOS 9.3.2 is still the newest and current officially supported operating system (iOS 10 hasn't launched officially yet) and will therefore be the software your iPhone or iPad will be restored to if you select the iTunes option to Restore and Update. But we'll get into that in a moment.

The only issue is that you'll have to restore from a pre-iOS 10 backup (see How to back up an iPad or iPhone), so any data or preferences you've saved since then will be lost - and if you haven't got an archived backup from your iOS 9 days (as Apple suggests doing before upgrading), you won't be able to restore your data at all. In that case all your data will be lost and you'll have to go back to a factory-default 'new iPhone' or 'new iPad' setup. Something to consider.

Anyway, removing the iOS 10 public beta is simple:

  1. Enter Recovery mode by turning off your iPhone or iPad, then holding the Home button (on the front, below the screen) on your iPhone or iPad. This can take a while, so don't give up after a few seconds. 
  2. When it says 'Connect to iTunes', do exactly that - plug it into your Mac or PC and open up iTunes.
  3. iTunes will tell you that it's detected an iPhone or iPad in Recovery Mode, and that this needs to be restored - click OK to agree to this, and then Restore iPhone or Restore iPad (as appropriate).
  4. Finally, choose the option to Restore and Update. iTunes will download the latest version of iOS 9 and install it on your Apple device.

Once iTunes has reinstalled a fresh version of iOS 9, you have a choice of either restoring from an old backup (remember, your iOS 10 back up won't work) or setting it up as a brand new iPhone. Simply select your preferred option, follow the on-screen prompts and viola! You're back on good ol' iOS 9.

Read more: How to reset an iPhone or iPad

How to downgrade from iOS 9.3.2 to an earlier version of iOS

iOS 9.3.2 is currently the most advanced version of iOS available to non-developer owners of compatible iPhone and iPad models. (We explain how to install iOS 9 here: How to update to iOS 9 on iPad or iPhone.)

Before jumping in and installing the new version, some people will be keen to know whether it will be possible to revert back to a previous version of iOS 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 9.3.2 to see if any errors are reported, if you are keen to try iOS 9.3.2 then you'll want to know two things: what steps to take to safeguard your data and settings before updating, and how to go back to the previous version 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 iOS 9.3 and want to go back, you can jump straight to our section on downgrading from iOS 9.3.2 to an earlier version of iOS.

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 9.3.2, 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 9.3.2:

  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 9.3.2. Next we'll look at how to go back to a previous version of iOS (and restore the backup we just created) from iOS 9.3.2.

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

How to downgrade from iOS 9.3.2 and reinstall an earlier version of iOS - the complete guide

Removing iOS 9.3.2 (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:

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 9.3.2 backups, for instance, 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 9.3.2 : How to tell if Apple has stopped signing your previous version of iOS

A few days after the rollout of a new version of iOS, Apple stops signing the previous version, at which point this procedure gets 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 9.3.2, but we'll look into any remaining methods of downgrading when we next update this article.

Good luck!