Apple Stops Signing iOS 8.4, Downgrades Are Impossible Now
Apple has just stopped signing iOS 8.4. This means it is currently impossible to downgrade to this version of Apple’s mobile operating system.
If you have a jailbroken iPhone, iPad or iPod touch, make sure you don’t upgrade to iOS 8.4.1 accidentally. Although it seems that this version is jailbreakable, currently there are no tools capable of hacking devices with IOS 8.4.1 on board. If you try jailbreaking your device and then something goes wrong, you will have to restore to iOS 8.4.1, not iOS 8.4.
Those who don’t care about jailbreak can upgrade to iOS 8.4.1 right now. Although some people claim this iOS version is unstable, for most users it works as it should.
In case you don’t know, iOS 8.4.1 can boast of a number of stability, security and performance improvements. In particular, it fixes some bugs found in Apple Music and patches the vulnerabilities used for Taig and Pangu jailbreak.
Apple usually stops signing the previous version of iOS several days or weeks after the release of the newer build. This is what has happened this time.