Low power mode is a useful feature when your iPhone battery is low. Before iOS 11, turning it on it required you to go to your settings and tap on the low power mode tab.
Now, you can add it to the customized control center and simply turn it on and off by swiping up for the control center and tapping on the low battery icon.
Before you can start enabling Low Power Mode from the Control Center on iOS 11, you need to add Low Power Mode toggle in the Control Center which can be added from the Settings menu.
Go to Settings – Control Center and tap the (+) sign on Low Power Mode. This will add Low Power Mode toggle in the iOS 11 Control Center.
Now you can start enabling Low Power Mode from Control Center on iOS 11.