As usual, one week after the release of iOS And iPadOS 15.3, Apple stopped signing versions 15.2.1. As a result, those who have updated their devices to the latest stable version will no longer be able to downgrade to the previous release.
iOS 15.2.1, we recall, was a minor update mainly focused on fixing an important HomeKit vulnerability discovered last year, a bug that had already been partially corrected by Apple with iOS 15.1. Even before that, with iOS 15.2, many new features had arrived including support for Apple Music Voice Plan, the App Privacy Report, the “heir contact” to leave your digital legacy, the key for macro mode and ProRes. in the iPhone 13 Pro and 13 Pro Max.
IOS and iPadOS 15.3 are also updates that focus mostly on the performance improvements and bug fixes. One of the most important concerns a Safari vulnerability that could have leaked the browsing history and Google ID data on the websites visited by the user.
Restoring to previous versions of iOS and iPadOS is not a commonly done procedure, but it can often come in handy for those who encounter significant bugs after updating to a new version. For example, iOS 14.7 had caused problems with unlocking Apple Watches paired with an iPhone with Touch ID, iOS and iPadOS 13.2 had imposed overly aggressive background management of apps.
The downgrade is instead used a lot by those who jailbreak their devices to change settings, install apps and non-certified tools. In fact, subsequent updates often close system vulnerabilities exploited to execute exploits used by jailbreak tools.
Signature blocking, however, is also used by Apple to try to keep users on the latest versions of its platforms by preventing excessive fragmentation.
Version 15.4 of iOS is currently in beta testing phase which, in addition to the usual performance improvement and bug fixes, will also bring many new functions including unlocking with the mask on iPhone 12 and later even without an Apple Watch, new emoji, the ability to enter the Green Pass in the Wallet and in the Health app and the Universal Control function.