The geometry is fine, this is simply a display issue when your tessellation is set low. On weaker machines this can be necessary to keep the app running smoothly. You can adjust it in the settings.
What he said. View it in visualization and it will look PERFECT! Whatever it is (lamp?)
Well, the quality is at the maximum and I’m using an iPad m5 with a lot of memory.
Anyway, thank you for the info 
Yes, it is the sample model, which brings the shapr3d itself. It seems that it is a bug because the visual quality is at the maximum, thank you for the info. 
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