How many cores does Shapr3D use on the iPad?
Do you have any benchmarks on when a 2021 iPad Pro starts to struggle to render objects (like number of bodies)? Any super complex models that you’ve tested on the iPad that you can share with the community so we can get an idea of the limits of Shapr3D on a very portable and pencil friendly device?
It depends on what you do. Certain things can be parallelized, while others can’t be run in parallel. Whenever it’s possible, Shapr3D is using as many cores as possible.
Rendering performance does not really depend on the number of bodies, but rather on the complexity of the surfaces. Rendering ten thousand cubes is much easier than rendering ten thousand bodies with complex surfaces. But generally speaking, performance should not be an issue for thousands of bodies. You can download complex assemblies from GrabCAD and load it on your iPad if you want to test it for yourself.
How about RAM? Can Shapr3D access more than 5GB and have you seen any performance gains with larger models and the 16GB of RAM over the 8GB?
Shapr uses as much ram as it can have access to. If you don’t have enough memory on the iPad, you won’t be able to open the design at all. So if you are planning on using large, complex models, buy the model with the biggest memory amount possible.
You read my mind 
I’m not sure how complicated the models I will eventually be working, so I just bought the 1TB/16GB iPad Pro 12.9" model to replace my smaller 11". The primary reason was for the screen real estate, so I figured why not. There’s no such thing as too much RAM.
Enjoy! I think you are going to have a good time with it 