1. Turn sketches, mockups and designs into web, iPhone, iOS, Android and Apple Watch app prototypes.

  2. Prototyping and collaboration for design teams

  3. The prototyping and specification software used by 87% of the Fortune 100. Beyond mockups, design interactive prototypes for business solutions, websites, and applications.

  4. Design is really about solving problems. UXPin is the UX Design Platform that gets that right.

  5. Fluid UI helps you prototype Android, iPhone, iPad or Windows 8 mobile apps with our custom libraries, or upload your own images for pixel perfect mobile

  6. Design interactive UI prototypes for modern interfaces.

  7. The most stunning HTML5 app for creating resolution-independent SVG mockups, wireframes & interactive prototypes for your next project

  8. Principle makes it easy to create animated and interactive user interface designs.

  9. Using Balsamiq Mockups feels like you are drawing, but its digital, so you can tweak and rearrange...

  10. The fastest way to design beautiful interactions

  11. The prototyping tool designers have been waiting for.

  12. Concept.ly - Free web & mobile(iOS,Android) prototyping and ui mockup tool