Forbes colleague David Shaywitz wrote more broadly (and brilliantly) about this in his piece earlier today: Handle With Care: Success of Digital Health Threatened by Power of Its Technology.
Every one of the businesses here are going to be making determinations about where you locate based on the quality of the workforce, how much investment you have to make in training somebody to handle a million-dollar piece of equipment.
Not a case but a handle: the FlyGrip is a little L-shaped piece of plastic that attaches to the back of your iPhone so you can hold and use the touchscreen with one hand.
They'd balance a spoon-shaped piece of magnetic rock on any flat surface, and since it was magnetic, the handle would swivel to align itself with the Earth's magnetic poles.