UXpin - Design is really about solving problems. UXPin is the UX Design Platform that gets that right.
StarUML - StarUML
Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Visual Paradigm - Looking for an affordable software with Enterprise Architecture tool, PMBOK tool, UML tool, Agile tool, BPMN tool and UX tool? Read this page for details.
Moqups - The most stunning HTML5 app for creating resolution-independent SVG mockups, wireframes & interactive prototypes for your next project
PlantUML - PlantUML is an open-source tool that uses simple textual descriptions to draw UML diagrams.