Brand.ai - Create a style guide & integrate with Sketch, Slack, & Gulp
Fluid for Sketch - Sketch plugin to make your responsive designs more efficient
MediaKits - The easiest way to create a media kit
Marvel for Sketch - Sync, play and record prototypes in Sketch!
Frontify Workspace - The overall tool for creative & design collaboration: - upload, manage & share assets
Anima App - Design, get feedback, convert to code, publish, iterate.