The most widely used tool in the same market is
color.adobe.com.

It has a minimal user interface that uses seven color ‘rules’ that lets the users create a color scheme comprised of five colors. The color rules are analogous, monochromatic, triad, complementary, compound, shades, and custom.
The main component of the UI is the central color wheel which you can use to make selections that change within a color “rule”. The palette can also be modified by using the RGB sliders, RGB value entry, or the HEX value entry, at the bottom of each swatch. Again, the color rule constrains the changes made to the palette.
Color Theory
Analogous colors are adjacent to each other on the color wheel with one main color and four accent colors. The main color is highlighted in the UI, placed in the middle by default, with the accent colors flanking it.
Monochromatic colors are from a single hue that vary in tints and shades of the main color.
Triad colors are usually three colors that are of equal distance from each other on the color wheel. Adobe Color gives five colors by varying the hue of the first three colors.
Complementary colors are direct opposites on the color wheel.
Compound color scheme gives highly contrasting colors of hues that are in the range of complementary colors.
Shades option lets the user pick one main color and returns five different shades.

Another tool that is currently utilized is
COLRD.com, which is a public community of color palettes that lets the user upload an image from which CORLD generates a color palette. There are options as to how many swatches are picked out per image and the user can shuffle the hidden color rule. It generates a library of the colors used in the image and presents it in 12 hues. These palettes and images can be stored to the user’s account. However, the UI is inconvenient because it does not let the user navigate between functions without returning to the homepage. Also, COLRD does not show what color rule it is using to generate the palettes.