It's called Snapguide. It allows you to create quick and easy (and stylish) DIY how to's and share them on the web. You don't need an iPhone to view the tutorials, but you do need one to create them.
I couldn't wait to make one, so I created a quick tutorial on how to make a chain out of jump rings. You can check it out here.
You can follow me to see upcoming tutorials.
I think I'm in love.