This links heavily into the following question: What are some great web-based prototyping tools? However I didn't want to limit the suggestions to "Web Based" tools, I have found and used the ...
I'm looking for a list of web-based prototyping tools and I'd like to build one up here by using StackExchange's democratic voting system. There are already some lists around the web, notably these ...
The app in question targets your typical mouse/trackpad + keyboard users. Actually having someone draw using pencil+paper (e.g. on a paper prototype) misses the point which is that it sucks to draw ...