I'm currently not satisfied with Apples ISO 6 and want to downgrade. Basically, I know there is a jailbreak out and was thinking if I jailbreak my ISO 6, will I be able to downgrade? and if so how?
Ok... on an iPhone 4 downgrading is possible. Only, though, if you have SHSHs (Blobs) saved for 5.1.1, or whatever iOS version you want to downgrade to.
If you don't have the blobs... then there's no way to downgrade. Jailbreaking is something entirely different than downgrading... neither of which go hand in hand. Your iPhone 4 can be Jailbroke on iOS 6. It's a tethered JB and there's quite a few issues w/ it that the Devs are currently working on.