One shot would be impossible. It uses 3 main pictures, one straight on picture, one picture of the back, and one picture of the front of the card on an angle. Using these 3 its able to identify the exact centering, edge wear, and surface scratches that are going to affect grading and give you a fairly accurate grade. I've used it on a few PSA submissions myself and so far I am very happy with its correlation to the grades on the cards i got back.

Congrats for the launch! I really like the live phone scan that estimates a PSA grade with centering/corners/edges/surface and raw-vs-graded comps? Would a demo video help you reach more people and get the product adopted? If so, feel free to try Fluxcut (www.fluxcut.dev) where the demo video in the landing page is made by Fluxcut.