I’ve mentioned a number of nice projects for iOS developers as of late from Facebook such as Chisel that enhances the lldb debugging console and Shimmer which allows you to add a shimmering effect to a UIView.
Here’s another nice free tool for iOS developers from the Facebook design team that makes it easy to create interactive prototypes called Origami that has just undergone a major update.
Origami provides an excellent toolset for prototyping with Apple’s Quartz Composer tool making working with Quartz Composer very easy, adding a number of new elements, and enhancing Quartz Composer with some nice features such as retina screen support.
To use Origami you’ll need Quartz Composer installed, and it can be downloaded from the Apple site here.
You can find Origami on the homepage here.
Make sure you don’t miss the examples.
An excellent toolset for quickly creating interactive app prototypes.