Anima App - Design, get feedback, convert to code, publish, iterate.
Color Palette Generator - Enter the URL of an image and find its color palette
Sketch Repo - Collection of resources for anyone who uses Sketch
Color Hunt - Curated collection of beautiful colors, updated daily
Git Sketch Plugin - Version control for designers
Coolors.co - The super fast color schemes generator! Create, save and share perfect palettes in seconds!