You Can Downgrade to iOS 10.3.3
If iOS 10.3.4 is giving you problems you can try downgrading to iOS 10.3.3.
Apple's currently signing on the iPhone 5's iOS 10.3.3 update which means you can take advantage of a loophole and drop back down in an effort to improve your device's performance.
If you're curious about how the downgrade process works, take a look at our walkthrough. It'll take you step-by-step through it all.
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