One of the most useful, if low-tech, features of the iPhone is its flashlight, which you turn on by tapping the Flashlight icon in Control Centre (get to it by swiping up from the bottom of the Lock screen or Home screen). But you don’t have to retrace your steps in Control Centre to turn the flashlight off. Instead, just swipe left partway on the Lock screen, as though you wanted to take a picture—you don’t even have to go far enough to switch to the camera. That turns off the flashlight without any need to fumble around in Control Centre.