Let us look at the Vibrance option in Pixlr Express. Pixlr Express is a free image editing App for Smartphones. If you haven't installed it already, you can read more about it on this link.
This is the edit mode of Vibrance. With the slider pointing at 0. You can move it to left or to right to decrease or increase the value.
This is the effect on Vibrance value (-50)
This is the effect on Vibrance value 50
So, see it for yourself.
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