It revived the Android menu button. root is not required.
Let's regain the menu display of the application.
In addition buttons can be displayed "Home" "Back" "Resents".
You can use as an alternative to the broken physical button.

[Basic functions]
 - Display of the menu button
 - position of the button size transparency color customize the icon
 - Display of the notification bar
 - the presence or absence of vibration

[Other buttons]
 - back button
 - Home button
 - application button recently used
 - Power button
 - button to increase the volume
 - button to lower the volume
 - mute button
 - Enter key button
 - space key button
 - the arrow key buttons
 - TAB key button
 - Page up button
 - page-down button

[Application]
Buttons can be added freely you can customize the behavior of the tap and long press.

[Keyboard switching]
When you press the menu button send the menu key from the keyboard (IME) call up the menu of the application being displayed.
When you press the button if the keyboard is not a menu button IME because the keyboard selection is displayed
Please temporarily switching. Then when performing the character input will return the keyboard with a single touch.

[Permission]
This app uses the user auxiliary services. (BIND_ACCESSIBILITY_SERVICE)
This will be used only to perform the same operation as the home button and back button.
If a physical button of Android devices is broken
This app is an alternative to the home button and back button to help the user.