Description:Button Mapper makes it easy to associate custom actions with your volume buttons, the Bixby button, or other hardware buttons on your phone. Reassign keys to launch any app, shortcut, or custom action. Assign actions by pressing once, pressing twice, and long pressing the keys on your phone. Root is not required
Features:
+long volume down to switch the flashlight
+ Double+tap your Home button to launch your favorite app or shortcut
+ Long press your home button to turn off the screen
+ Double+click the back button to open your notifications
+ Change your back and the last apps buttons
+Use the volume keys to adjust the screen brightness
+Press +long to toggle the Do Not Disturb mode
Required Android Versions: Ice Cream Sandwich [4.0.3–4.0.4] - Jelly Bean [4.1–4.3.1] - KitKat [4.4–4.4.4] - Lollipop [5.0–5.0.2] - Marshmallow [6.0 - 6.0.1] - Nougat [7.0 – 7.1.1] - Oreo [8.0-8.1]