A feedback that I repeatedly hear from users is that the Kanban application is very difficult to scroll on mobile devices: In order to scroll vertically, one has to touch a very thin (unmarked) margin besides the items (and start "dragging"). If one fails to touch the margin, the closest item is accidentally dragged and dropped, often causing an unwanted reordering of the items.
Similarly, scrolling horizontally seems to cause an accidental reordering of an entire column.
It would be great if there were a (relatively) fail-safe option for horizontal and vertical scrolling in the mobile variant of the Kanban application. Maybe if there was a button to enable/disable the drag'n'drop functionality of items and columns? Not sure though.