Show HN: Linear Chess – Normal Chess, on a 1D board

Very slightly related: "1D Chess" https://rowan441.github.io/1dchess/chess.html (HN discussion https://news.ycombinator.com/item?id=47719740 | 1001 points | 46 days ago | 186 comments)

I am on mobile. I can select a pawn, but not move it touching the destination. What is the trick?