Uizard - Design made easy – powered by AI
Anima App - Design, get feedback, convert to code, publish, iterate.
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Fluid for Sketch - Sketch plugin to make your responsive designs more efficient
Git Sketch Plugin - Version control for designers
InVision Studio for UI Designers - Free video course on InVision Studio