Oh man, my buddy Dave almost did the same thing with a scissor lift at his last job site. They had this phone app for checking fluid levels, but it also had little up/down arrows. He thought it was just a dumb demo. He tapped "extend" while standing next to it, and the thing actually JERKED and started going up. He nearly dropped his phone. The app was for real controls, not a game. He said it was terrifying knowing his phone was moving actual industrial equipment.