On Android Chrome, "flinging" the scroll really far really fast sometimes keeps scrolling long beyond when I would have expected it to stop. But the page is so gigantic that that might just be the expected behavior.
FYI, I've also noticed that on Android (but not on desktop Chrome) sometimes single-tapping to remove a black square will leave a stray X behind. I think this is not a logic bug but rather a mobile input-recognition problem — that on mobile a single-tap is sometimes being recognized as a single-tap followed by a double-tap. (Quickly double-tapping an empty cell usually marks it with an X; although quickly double-tapping a filled cell usually just clears it, no X. So the symptom here is "I meant to single-tap a filled cell, but the game acted as if I'd single-tapped and then double-tapped the same cell again.")
FYI, I've also noticed that on Android (but not on desktop Chrome) sometimes single-tapping to remove a black square will leave a stray X behind. I think this is not a logic bug but rather a mobile input-recognition problem — that on mobile a single-tap is sometimes being recognized as a single-tap followed by a double-tap. (Quickly double-tapping an empty cell usually marks it with an X; although quickly double-tapping a filled cell usually just clears it, no X. So the symptom here is "I meant to single-tap a filled cell, but the game acted as if I'd single-tapped and then double-tapped the same cell again.")