1. HTML5 all-in-one mockup & prototyping tool that exports completed interfaces to working HTML + Javascript

  2. Tandem is a visual editor for web development.

  3. Library of 537 blocks for desktop and mobile prototyping

  4. The Best Animation App on Mobile Devices.

  5. WireframeSketcher is a wireframing tool for creating wireframes, mockups and prototypes for desktop, web and mobile apps. It's a desktop app for Mac, Windows and Linux, and a plug-in for any Eclipse IDE.

  6. Create custom forms with personalized layouts and designs

  7. Mockup & Wireframe toolkit for PowerPoint

  8. SwordSoft Layout is an desktop application that makes it very easy for you to create, preview, and...

  9. NinjaMock is the faster, better and funnier way of making mockups

  10. FlairBuilder is a user interface prototyping tool for easy authoring of interactive website...

  11. PixelServed is the fastest way to preview UI designs created with any creative

  12. Flexible and powerful desktop application for designing and uploading professional-quality websites.