Here are some I use regularly, each serves me a different purpose:
Axure ($289, $589)
Keynote ($20.00)
Xcode + Origami ($100)
Axure is really good for creating mobile/desktop prototypes and it supports responsive design as well as interaction design in fine detail. Keynote is good for setting up something simple to demonstrate an idea to clients. XCode and storyboarding + origami for native iOS prototyping.
Here are some I use regularly, each serves me a different purpose:
Axure ($289, $589)
Keynote ($20.00)
Xcode + Origami ($100)
Axure is really good for creating mobile/desktop prototypes and it supports responsive design as well as interaction design in fine detail. Keynote is good for setting up something simple to demonstrate an idea to clients. XCode and storyboarding + origami for native iOS prototyping.