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Users running iOS 8.1.3 versions and above can no longer downgrade to iOS 8.1.2, the last jailbreakable iPhone firmware version Reuters

Those looking to jailbreak their iPhone or iOS device by downgrading to iOS 8.1.2 can no longer do so as Apple has stopped signing the last jailbreakable firmware version of the mobile OS. Users currently on iOS 8.1.2 will still be able to jailbreak their iPhone, enabling the installation of software, tweaks and tools not available on the App Store. However, there is a caveat.

If a problem arises where a full iPhone restore is required, users will be forced to upgrade to the latest version of iOS 8.1.3 while losing the jailbreak altogether. This is due to the way Apple handles the upgrade and restore process. When users want to install a version of iOS on their device, iPhones, iPads and iTunes communicate with an Apple server, which then dictates what version of iOS is allowed to be installed by issuing software signatures.

While Apple prevents users from restoring to older versions of iOS, there are some measures iPhone users can take to prevent the loss of their jailbreak, which are extensively detailed in a post on Reddit.

With the release of iOS 8.1.3 in January, Apple introduced a number of fixes for iOS 8, including security patches which closed the software flaws used by Chinese developer teams TaiG and Pangu to create their respective jailbreak tools. It’s unknown when the next jailbreak will surface for iOS. But it’s unlikely to happen until after Apple releases an iOS version that adds support for the Apple Watch, which is set to ship in April.

The company is said to also be working on the next major release of its mobile operating system, iOS 9. The upgrade is expected to be the “Snow Leopard” of iOS, with Apple developers placing focus on fixing bugs and optimizing iOS 9, rather than introducing tons of new features.