How on Earth is this patentable?
The mobile manufacture element is only a tiny part of the claim, what is actually being claimed here is essentially a 3D printing bureau service of the kind that has been around for 20 years. The only difference I can see is the introduction of a library of third party designs that can be selected by the user, instead of needing to supply a design at time of order. Hardly a groundbreaking step, indeed it could be argued that making a request "Send me one of your demo models" to a 3D printer vendor is prior art here.
Yes, I know the US patent system is hopelessly broken but even so I surprised they would think it worth the time even trying to patent this.