I had a data visualization class as an "easy optional" in grad school. The professor told us "y'all are mathematicians and don't understand color. Pick some artwork you like and put it through Adobe Color instead of trying to make your own messes."
That's good advice. Just like in software where you shouldn't roll everything yourself, in design there's plenty of space to defer to other experts who've thought through this stuff.
There's already enough problems to solve building an app. You should be obsessing over the hex value of colours.
