I see the use in the physical product when prototyping but I'm worried it would encourage the use of more refined interfaces. I usually use post-it notes on my iPhone and I love the limitations it presents as it forces me to keep it simple. The use case (IMO) remains in the weird stages between Sketch and Analog mockups.
Found this simple prototyping tool while looking at ways to do user stories. It lets you download a 3D printed model and a paper template that you can just use to assemble and draw your mobile UI.
This is an awesome prototyping tool. Would be perfect for creating quick mockups of designs and doing low-fi user testing. Get one of these in your hands asap.