Brand.ai - Create a style guide & integrate with Sketch, Slack, & Gulp
PSD to Sketch Design Converter - Convert a Photoshop design to a layered Sketch file for free
Sketch Styler - Sets the most similar style to unstyled layers automatically
Zeplin - Collaboration app for UI designers & frontend developers
Sketch Repo - Collection of resources for anyone who uses Sketch
Frames for Sketch - Create awesome websites & apps using powerful design system