KnockOn

KnockOn is a small Android utility that lets you control the screen with double taps, focusing on quick wake and sleep actions without relying on physical buttons.

It is for anyone who prefers gesture-based control for screen on and off, especially on devices with an OLED display.

Quick taps, quicker screen control

KnockOn centers on a simple idea: use double taps to wake the screen and to put the device to sleep. It also supports double tap to lock, giving you a fast way to end a session without hunting for a side key. When it works well, this approach can feel more convenient than pressing a hardware button.

Where the wake gesture fits best

The app’s double tap to wake is described as OLED-only, with a notable technical compromise: it can show a black screen so the display is effectively on. KnockOn also warns that battery use may be higher with wake enabled, and it advises against using that wake behavior on LCD screens.

Adjustments that help it match your habits

KnockOn includes settings to tune double tap speed, along with a triple tap option for those who want an alternate trigger. There is also a sleep time setting intended to reduce power consumption, plus a homescreen widget that can turn the screen off.

Compatibility notes and small caveats

For devices using fingerprint unlock on Android Marshmallow, KnockOn calls out a platform limitation that can affect screen locking, while still allowing double tap to sleep via a fingerprint-focused mode. As with many gesture utilities, it is also described as having occasional bugs and quirks, even though the core gestures can work well on OLED devices.