System UI Tuner not enabling How do I enable System UI Tuner on my Lenovo Vibe K4 Note.
It is not enabling on long press of quick settings button in the notification panel.
if you are on marshmallow long press the "GEAR" icon for 5 seconds

   

(you should see a prompt that says ui tuner enabled)


then go to settings and you should see the ui tuner in the settings.


Link with tutorial here http://gadgetguideonline.com/android/android-marshmallow-guide/how-to-use-system-ui-tuner-in-android-marshmallow/