I've been reading it for a while, definitely "worthy", I'm a UI designer and I've been designing iPhone applications for more than one year and I still find it

I've been reading it for a while, definitely "worthy", I'm a UI designer and I've been designing iPhone applications for more than one year and I still find it extremely interesting. There are a lot of things that you take for granted without thinking about the why you are doing it, this book explained to me.