OK, so it’s not a physical button. It is a completely new way to trigger a feature on-screen without using the touchscreen, which is pretty great. Dubbed “Back Tap”, it allows users to use the rear case of the iPhone as a button. Tapping on the aluminium or glass case at the back of the handset can trigger a host of new functions, like launching the Control Centre, or switching on the Mute function, turning the volume up or down, or taking a screenshot. You can also use “Back Tap” to trigger any of the Siri shortcuts you’ve already set-up on your iPhone.
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