Currently Apple has closed the iOS 8.1 system verification, which means that iDevices that has been upgraded to the latest version of iOS 8.1.1 have been unable to downgrade to iOS 8.1 version.
In October this year, Apple released the iOS 8.1 version of the system, and this version is also the first time Apple will officially Apple Pay mobile payment services into their own systems.
Of course, if you have upgraded to iOS 8.1, then you can decide whether you want to upgrade. If you have not upgraded or are currently using can not jailbreak firmware version, so you only have the option to upgrade to iOS 8.1.1 to jailbreak.
iOS 8.1.1 is currently supported by the system models include iPhone 4S, iPhone 5, iPhone 5C, iPhone 6, iPhone 6 Plus, the fifth-generation iPod Touch, iPad Air, iPad Air 2, iPad Mini, iPad Mini 2, iPad Mini 3 , iPad 2 and iPad 4 and other models.
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