Back up before downloading
Back up your devices
First, a big warning about downgrading your device — it will be completely wiped to factory settings in the process. If you have an archived backup from a version of iOS at least as old as the version you are downgrading to, you will be able to restore
that backup; if not, you are going to be starting over from scratch. Before you start this process make sure to back up your iPhone. That includes backing up any photos, videos or other content from your device that
you wouldn't want to lose. If you've installed iOS 15 or iPadOS 15 through Apple's developer program or the public beta now it's been released, you may decide you want to downgrade because of usability or stability
issues. Keep reading to learn how it's done..
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