When the screen is small (say 1024 pixels horizontally) the morphology helper for verbs doesn't fit the screen horizontally. It helpfully has the little left and right buttons to scroll it. Emphasis on little. They are hard enough to hit with a mouse accurately, but just forget about it on a touch screen. Please make them bigger. Or better yet, make the helper support dragging so I can just click and drag left and right to scroll through the options.
Also, it is very difficult to hit with a stylus on penabled screens because the edge of those screens tends to be bit inaccurate.
Further, it isn't really useful for each click to only move a few characters. Each click should fully expose at lease one more column of options.