With an IPSW file, you can upgrade or downgrade your iOS system manually without iTunes. IPSW file is the Apple Device Software Update File, with an extension '.ipsw.' An IPSW file contains data used by Apple to conduct system restore and update to iOS, iPadOS, tvOS, and HomePod firmware.
In this article, I will share how to install an IPSW file on iPhone without/with iTunes. Many third-party tools can help you install an IPSW file to avoid some unexpected installation failures. In this case, you need to manually install an IPSW file to restore your iPhone system to a previous version. If you have accidentally upgraded your iOS system to the latest version and want to roll back, there is no way to do this via neither the 'Restore Backup' nor the 'Restore iPhone' option in iTunes.
