Balsamiq is one of the most interesting prototyping tool I have found on the web. It’s powerful because it can visualize all the elements you need to build an UI with a selection of stunning interface elements (yes, they have that sketched style we all love). It is free as webapp but you can buy a license to enjoy it in all its beauty.
I have been trying to design a mobile version www.venere.com (my company) by using the iPhone elements Balsamiq provides you. As you can see below, the effect is pretty nice!
