The firmware is an improved version of the mobile platform released by the device manufacturers. However, the new is not always better than the old, so if, for example, you are not satisfied with the new firmware on the iPhone, you can roll back it to the previous version.
Instructions
Step 1
Install iTunes software on your computer to exchange data with iPhone and install updates. You can download it from the official Apple website in the "iTunes" section. You will also need a distribution kit of the firmware version to which you would like to return. You can find it but one of the Western or Russian sites dedicated to Apple products. Here you will also find detailed instructions on rolling back to different firmware versions, as well as on installing updates and difficulties that may arise in the process.
Step 2
Connect your iPhone to your computer via USB cable and launch iTunes. Wait until the end of the procedure for determining the phone model, after which it must be switched to DFU mode. Press and hold the Home key and the Lock key at the same time for ten seconds. Release the lock button while continuing to hold the Home button for a few more seconds. If you do everything correctly, iTunes will display a notification that the device is in recovery mode. Release the keys you pressed earlier.
Step 3
Press the special keys on your computer keyboard depending on your operating system: on Windows, this is the Shift key, and on Mac, Alt. Then, in the window that appears, click the "Restore" button. Specify the path to the downloaded file with the previous version of the iOS mobile platform. After that, the system rollback procedure will automatically start, which can take from 10 to 20 minutes. During this time, do not press any keys on the device, do not disconnect it from the computer or run third-party applications on it, otherwise the phone may fail beyond repair. Upon completion of the rollback procedure, your iPhone will be rebooted with the restored firmware version.
