Two at a Time

Spoiler: Video Solution

Nah. I didn't like the move of P and R like that.

Manageable instability. No matter what happened an R never got stuck or isolated on my ipad, so I enjoyed it. I wonder if on some devices P might be able to push that ball as he seemed very close to doing it.

simple and beautiful, although I had to restart several times because P kept falling into the water

@Andrea gerbillo - As @ridgerunner stated ' Manageable instability'. P can fall off and as per my video, I placed B to catch P from falling as P walks onto B and then back into the ball zone. Thanks for playing.