A descrição de Back Button

Back Button help you limit the use of physical keys
Back Button help you easily return to the previous screen or double-click to return to the Home screen.
It can simulate the system button like back button, home button and recent button. it can also let you pull down the notification bar quickly.
Main Features of Back Button :
 Ability to change color of background and icon
 Ability to change icon of Back Button easily with many pretty theme
 Easily display functions in the notification bar: Home, Recents, Settings
 You can move the button to anywhere on screen
 Gesture Setting for Floating Button (One click, Double click and Long click)
 On off vibrate when click
 Change theme back button
Note: In order to use it, please turn ON "Back Button" service from "setting -> Accessibility Option."
*Back button uses Accessibility Services.
Accessibility service is to use the functions of "Back button", "Home button", "Resents button" and "Notification bar", and it will not be used elsewhere.
Thank you for use Back Button. Download and rate 5 star for Back Button - Home, Recent ,Back Pro support to developer.