ANDROID grayscale mode direct and through developer mode also make accessibility shortcut

Описание: Lenovo K3Note quick setting for enabling gray scale mode/monochrome/Black on white mode in Android 6 Marshmallow, also learn how to make shortcut of accessibility setting on Home screen for quick access to color correction mode.

How to turn on Gray scale mode in android 6 / Marshmallow easy setting

or enable through developer mode setting for older version of Android

How to make accessibility setting shortcut for quick enable disable gray-scale mode