Raise to Wake is what allows your iPhone to become active when you lift it from a flat surface.
This setting is especially useful if you have to use your iPhone in an area with little to no light, as it will immediately light up when you lift it.
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What Raise to Wake is on your iPhone, and how to turn it on or off
However, sometimes you might not want a simple motion to be able to turn your phone active.
This can be particularly true if, for example, you put it in your pocket and don't want it to turn on when you move.
Either way, you should know how to turn your iPhone's Raise to Wake function on and off.
1. Open Settings.
2. Scroll down to and tap on Display and Brightness.
3. Raise to Wake is the middle item in the menu. If it's on, the button next to it will be light green.
4. To turn it off, tap on the toggle so it doesn't show green.
When Raise to Wake is off, you will have to hit the home button (the button on the bottom of your iPhone) to awake your iPhone so you can use it.