Double Tap to Sleep ❕ This feature requires Niagara Pro and a phone that runs at least Android 9. We're also offering a workaround for older phones that are rooted; you can read more about it here. This feature lets you turn off the screen quickly by double-tapping on the alphabet (or on the screen's left side). To enable the quick-lock gesture, go to Niagara Launcher’s settings > Features > Quick lock gesture. Why does the gesture only work on the alphabet? If you could also double-tap on the home screen or app list to lock the screen, every app launch would take longer. That's because Niagara Launcher would have to wait a bit after you tap on an app to check if you're doing a single-tap or double-tap gesture.