The real delight point for me was how painless it was to mark 700 words as already known and pickup a bunch of fairly common words i am not comfortable using (like “allerdings” and “eigentlich”) using that scroll-to-set-learned control.
That one took 3 completely different iterations and bunch of tweaking to get right. For example, when you open in, it scrolls a bit to the first word. When it did not scroll, a friend of mine was looking at it helplessly, trying to scroll on the left side with no success. UX is so difficult.
