With iOS 14, Apple introduced a back tap gesture that you can use to launch any app. Google has been working on a similar feature with the first developer preview of Android 11 and added new capabilities with the second developer preview. However, the software giant decided to remove it in the following beta releases but that did not stop a developer from porting the feature to work with most Android phones.
When you install and open Tap, Tap, there will be four sections namely Gesture, Actions, Gates, and Feedback. You can find the aforesaid device model options in Gesture section. In Actions, you can define the activities to perform once you double-tap. Available options include launching Assistant, camera, or an app of your choice, taking a screenshot, or toggling flashlight.
