To use the flashlight, tap the icon to turn it on and off. If you have an Android that doesn’t offer shortcuts, you’ll be able to access the flashlight in the Quick Settings panel when you swipe down from the top of your screen. Motorola phones can turn on their flashlight by shaking their phones and people with OnePlus phones can draw a “V” on their phone’s screen if it’s set up in Settings > Gestures. [2] X Research source

If your iPhone has a Home button, the flashlight will not be an icon on your lock screen. Instead, you’ll need to access the Control Center and use the flashlight icon there. Or you can ask Siri. [3] X Research source