The act of reverting an Apple device, such as an iPhone or iPad, to a prior version of its operating system, specifically moving from iOS 26 to an earlier iteration, constitutes a software downgrade. This process typically involves using a computer and specialized software to install the older iOS version onto the device, replacing the existing one. For instance, a user experiencing compatibility issues with certain applications after updating to iOS 26 might seek to revert to iOS 25 to regain functionality.
The significance of this action stems from several factors. Older iOS versions may offer improved performance on older hardware, resolve compatibility problems with specific apps or accessories, or allow users to retain access to features removed or altered in newer releases. Historically, the ability to perform this has been of interest, although Apple typically discourages and actively hinders such practices to promote the security and feature enhancements present in the latest software releases. Apple generally stops signing older iOS versions, making the process difficult or impossible without resorting to unofficial methods, which carry inherent risks.