ProtoShare is a web-based, collaborative wireframing and prototyping tool. It hosts a WYSIWYG drag-and-drop interface, as well as advanced components users can customize.
What's new in Version 6.3: a community library of customizable Stencils & Widgets and an expansion component styling options.
Wireframe Websites. Prototype Applications. Prototype Mobile Apps. Iterate on your ideas, get feedback, then mark and track decisions made.