Color Palette Generator - Enter the URL of an image and find its color palette
Sketch Palettes - Sketch plugin to save and load colors into the color picker
Material Palette - Generate and export your Material Design color palette
Colorion - Curated color palettes with search and tags support
Klart.io Colors - A data-driven collection of beautiful color palettes 🌈
Palettte App - Create, analyze and edit smooth color palettes