Apple has officially released iOS 10.3 for the iPhone, iPad and iPod Touch, adding a number of neat features and improvements to enhance the overall experience.
The new iOS 10.3 brings wider SiriKit support, a new Find My AirPods feature, a new file system, new features for app developers, CarPlay updates and more.
While some might love the latest iOS 10.3, others might not like the new OS version that much and would rather they didn't upgrade. For the latter category, the good news is that it's fairly easy to downgrade from iOS 10.3 to iOS 10.2.1.
It's worth pointing out that you can only downgrade during the small window while Apple is still signing iOS 10.2.1. This window typically lasts for roughly a week after a new OS version rolls out. Apple is still signing iOS 10.2.1 at the time of writing, but it's best to check the status before attempting to downgrade.
iOS 10.3 Downgrade Prerequisites
Before proceeding with the downgrade, there are a few prerequisites to consider so that everything goes smoothly. First of all, make sure that you have the very latest version of iTunes installed. Since Apple is no longer signing older iOS versions, it's only possible to roll back to iOS 10.2.1.
It's highly recommended to make a backup of all files and content stored on your iOS device so that you can recover the data afterward. You can make a backup either via iTunes or via iCloud. Since downgrading entails wiping your iOS device clean, it's essential to have a compatible backup for later restoring.
With this out of the way, let's move on to the actual downgrade, which entails just a few easy steps.
How To Downgrade From iOS 10.3 To iOS 10.2.1
First off, download the IPSW file for iOS 10.2.1 based on your device model. Be extra careful at this step, as you need to download the correct firmware for your iOS device or it won't work. As a side note, if you're using Safari to download the firmware file, make sure that the auto-unzip feature is not enabled. Alternately, just use Firefox or Chrome, or rename the file as .ipsw instead of .zip.
Next up, fire up iTunes and connect your iOS device to your computer via a USB cable. If Find My iPhone is enabled on your device, head over to Settings > iCloud > Find My iPhone and disable it.
In iTunes, find your device at the top left corner, select it and click Restore iPhone while simultaneously holding down the Option key on Mac or the Shift key on a Windows PC. A pop-up window should appear. From here on, you just need to select the iOS 10.2.1 IPSW firmware file that you downloaded earlier, and select Restore and Update to proceed.
The next screen will give you some details regarding iOS 10.2.1, so just hit Next and Agree. Once that's done, leave it to iTunes to verify the firmware and install iOS 10.2.1 in your iOS device.
After a few minutes, you should see the white "Hello" welcome screen on your iPhone, iPad or iPad Touch, which means that you've successfully downgraded from iOS 10.3 to iOS 10.2.1. All that's left now is setting up the device by following the on-screen instructions, then restoring from the iOS 10.2.1 backup.
If, on the other hand, you got an error message saying that your device is not eligible for that build, it means you downgraded the wrong IPSW firmware file for your device. Check again and download the right one, then go through the process from the beginning.
