Apple wants to keep your iPhone and iPad up-to-date. But you may want to go back to an older operating system. This is especially true if you’re trying out a beta version of iOS on your iPhone or iPad.
When a new stable version of iOS comes out, it’s usually only possible to downgrade back to the old version for a few days, although there’s a trick you can use. It’s easier to downgrade to the current stable version if you’re trying out a beta version of iOS.
Downgrade From Beta to Stable
If you’re using a beta, or preview, release of iOS on your phone or tablet, downgrading is easy. This process will erase everything on your iPhone or iPad, however. Device backups created using the beta version of iOS won’t restore to the old version of iOS, so you’ll need to either restore an old backup or set things up from scratch afterwards.
To restore your device to the stable version of iOS, you’ll need a Mac or PC running iTunes and a cable to connect your iPhone or iPad to that computer. Turn off your iPhone or iPad by holding down the Sleep/Wake (Power) button until the Power switch appears and sliding it to the right. Plug the cable into the computer, but not the iPhone or iPad. Press and hold the Home button on your iPhone or iPad — and keep holding it down. Plug the cable into your iPhone or iPad and keep holding the Home button down until the “Connect to iTunes” screen appears. You’ll see a cable pointing at an iTunes icon.
Launch iTunes if it doesn’t automatically appear. iTunes will inform you that there’s a problem with your device. Click the “Restore,” button and then click “Restore and Update.” iTunes will wipe the data stored on your iPhone or iPad and reinstall the current stable version of iOS rather than the preview version of the iOS software is was previously running.
If you have a backup created prior to installing the beta version of iOS, you can click “Restore Backup” from the device’s screen in iTunes to restore it onto the device after iTunes finishes restoring its operating system.
Restore Using an IPSW
Apple only allows you to load “signed” firmware images, or versions of iOS, onto its devices. Apple generally stops signing the previous version of iOS a few days after a new version is released.
This means that it’s often possible to downgrade back to your previous version of iOS for a few days after you upgrade — assuming the latest version was just released and you upgraded to it quickly.
To do this, you’ll need an .ipsw file. These may be stored on your computer if you used iTunes to upgrade to them, but they’re regularly deleted to free up space. You’ll probably need to download the IPSW file from a website like IPSW.me. Remember: You can only restore iOS images marked as signed. If the version of iOS you want to restore is marked as unsigned, you just can’t restore it.
Once it’s downloaded, connect your iPhone or iPad to your computer and open iTunes. Click over to the device’s page in iTunes.
On a Mac, hold down the Option key and click the “Restore iPhone” or “Restore iPad” button. On a Windows PC, hold down the Shift key and click the “Restore iPhone” or “Restore iPad” button. You’ll see a file browser dialog — browse to the downloaded .ipsw file and double-click it to restore that specific version of iOS to your device.
Save SHSH Blobs So You Can Restore Later
Those are the only two official ways to downgrade to previous versions of iOS. You can either downgrade from a beta version to a stable version, or downgrade to the previous stable version during a short window where the old IPSW files are still signed by Apple.
But, if a version of iOS is signed by Apple, you can use a tool to capture that “authorization” to run the previous version of iOS — in the form of “SHSH blob” files. These are device-specific digital signature files that control which versions of iOS can run on a device. Once you’ve received that authorization for your device, you can keep those files and restore that old version of iOS at any point.
For example, if you’re using an older version of iOS with a jailbreak available but you want to play with the current version, you’d want to get local copies of those SHSH blobs before upgrading to the current version. This way, you can then downgrade to the older, unsigned version and continue using your jailbroken software.
You can use TinyUmbrella — and possibly other tools — to create local copies of these SHSH blobs. Afterwards, you can use it to force iTunes to restore older IPSW files.
Apple doesn’t really want you running a previous version of iOS on its devices. Apple might occasionally let you downgrade to a previous version of iOS if there’s a big problem with the latest version, but that’s it.
You can choose to sit on the sidelines, if you like — your iPhone and iPad won’t force you to upgrade. But, after you do upgrade, it’s not generally possible to downgrade again.
Image Credit: Olle Eriksson on Flickr