Mirror
The phone's front camera takes over. Your face drives it, and there is no marble to roll.
The front camera takes over and your face drives what happens on screen. There is no stick, no world spin, and — deliberately — no rolling and no score.
It exists to prove the most extreme version of the idea: that a mode can replace the input method outright and the game around it still holds together. On that narrow question it works.
Whether it ships is genuinely undecided. It would need a short objective and a real ending first, and a face-tracking privacy policy to go with it. Being unfinished on purpose is different from being finished, and this is the former.