Reverting an iPhone, iPad, or iPod Touch to a previous operating system version is the process of uninstalling the current iOS software and installing an older, supported version. This action might be considered, for example, when experiencing performance issues or incompatibility with older applications after updating to the latest iOS release.
The ability to revert to an earlier operating system version can provide a temporary solution for users encountering software bugs or a preference for a previous interface. Historically, Apple has discouraged the practice of downgrading, primarily due to security concerns and the desire to maintain a consistent user experience across all devices. Apple typically signs only the latest iOS version, preventing users from easily installing older versions.