That’s because the only way to correct any critical problems that an upgrade might cause is to produce another complete upgrade to supersede it, because there is no quick fix process for an existing full upgrade that itself was released too quickly. In other words, the cost of Apple’s commercial decision to keep you on a one-way path of iPhone and iPad upgrades is that the company can’t easily afford to rush out emergency upgrades as quickly as it might otherwise like to (or as quickly as you might want). That’s because Apple doesn’t want users to be able to downgrade on purpose to reintroduce old bugs that they now know can be used for jailbreaking devices or installing an alternative operating system, even on devices that Apple itself it no longer supports.Įven if you completely wipe and reinstall your iDevice from scratch via a USB cable, using the built-in DFU ( device firmware update) utility, Apple’s servers know what version you were using before the reinstall, and won’t let you activate an old firmware image onto a device that’s already been upgraded past that point.

The last point above is surprisingly important, given that Apple absolutely will not allow you to uninstall full-on system updates to your iPhones or iPads, even if you find that they cause genuine trouble and you wish you hadn’t applied them in the first place.

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