Which is the Best Color Tool for creating great color combinations? Does anyone know a good mac app?
I feel your pain. Been looking for seemingly ever for a tool that can hand me a brilliant solution on a plate, but among the dozens and dozens of sites I've bookmarked, it doesn't exist as of yet.
You're stuck with making your own choices, but using the 60/30/10 rule (60% of the scheme should be your neutral/ground color, 30% your brand color, 10% your alert/click me color) for websites and apps is still your best bet.
As far as guidance in choosing which colors to use, if you don't have a brand color to start with, page through one of the color swatch galleries (like Color Hunt or Picular or Color and Color or Adobe Color until you find something that matches the project requirements, and once you have that, here are some of the more useful/interesting sites I've found:
Palx will generate a spectrum of shades and tints sympathetic to your brand color.
Color Designer will generate tints, shades and color harmonies based on a single color, which you can use to build your palette color by color.
Make Tints and Shades will generate groups of tints and shades based on as many colors as you want.
Eva will use your brand color to generate compatible tint/shade strips for the success, info, warning, and danger colors used in UI kits.
Circle Journey enter your brand color and switch up the Colour Type/Base Colour dropdowns to get color suggestions that are a bit more unusual than standard complement/analogue and so forth.
Geenes is a bit more inspirational/fun than practical, but it generates a color strip that varies by hue, saturation, tint and shade and presents it in an app screen mockup. A bit crude at this stage, but pleasing to look at.
Colorbox generates a color strip based on hue, saturation, and lightness. Not targeted at building a site/app scheme, but useful for exploring variations on a color for use in illustration.
AND AS LONG AS I'M DUMPING ALL MY LINKS, HERE ARE TWO ARTICLES WORTH SKIMMING:
Have you tried https://paletton.com/ ?