Why There's a Delay Before Your iPhone Screen Turns Off (and How to Eliminate It) - Lifehacker

If your screen seems sluggish when going to sleep, it's not just your imagination.

Ever noticed that your iPhone display is a little sluggish about going to sleep? Pressing the Side button on older iPhonesbefore the introduction of Face IDwould immediately shut off the screen. Newe… [+2413 chars]

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