For performance reasons and to support unlimited number of rows and columns, in pqgrid, cells are rendered only in the viewport, which means cells are created and destroyed continuously as the view is scrolled.
In touch devices, scroll event is fired at a longer interval, resulting in skipping of rendering and painting of some of the new cells.
This skipping happens only when the view is scrolled.
When scrolling is stopped, all the cells are rendered in viewport, thus from our viewpoint this is not an issue and there is no plan to change it.