One of the many security updates included in iOS 9.1 happened to block the iOS 9.0.2 Pangu jailbreak that the team of hackers released to the public last week. Unfortunately, we have to take the good with the bad when we upgrade our iOS devices, but iCrackUriDevice has instructions for how to downgrade back to iOS 9.0.2 in case you still want to jailbreak.
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