Well, here is a quick and easy solution to decrease screen's reflection and have rich colours without any app on G3!!
1) Open Menu and go to Settings.
2) From here, scroll down and go to Accessibility.
3) Scroll down and tap Colour Adjustment.
4) Now Turn It On and adjust colour in such manner as shown in screenshot.
1) Open Menu and go to Settings.
2) From here, scroll down and go to Accessibility.
3) Scroll down and tap Colour Adjustment.
4) Now Turn It On and adjust colour in such manner as shown in screenshot.
5) Now you have rich and less reflective display. Remember swiping down or up will add or subtract contrast respectively. Similarly swiping left or right will change colours.So, Only Swipe Straight Down Without Getting Left Or Right. Otherwise you will change G3's Original colours.