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I'm the owner of iPhone 4. Is there any possible way to downgrade from 7.02 to one of the previous firmware versions? The whole point is I don't have and have never had SHSH blobs and have never jailbroken my phone. The ideal is to get back to iOS 4, but even 5 and 6 would be fast enough for not annoying me all the time with iOS 7's incredible slowness. If there is some way to do that I will be absolutely happy. Thanks.