UXpin - Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Sketch - Professional digital design for Mac.
Moqups - The most stunning HTML5 app for creating resolution-independent SVG mockups, wireframes & interactive prototypes for your next project
Invision - Prototyping and collaboration for design teams
Balsamiq - Balsamiq. Rapid, effective and fun wireframing software.