For some reason, every prototyping tool that I've tried has issues with the physics of the scrolling. ProtoPie, Flinto, Figma all have scrolling that doesn't feel QUITE right. At points, the scrolling is faster than the flick of the finger is, sometimes the bounce effect is cut off short prematurely. It's difficult to explain the issue exactly.
The only prototyping player with REAL iOS scrolling is Sketch Mirror. I don't know if ProtoPie and Sketch use different scrolling mechanisms, if one is native and the other one is proprietary, but if this issue could be looked into, it would tremendously improve the believability of my Pies.