One of the oldest and fiercest rivalries in professional sports is between the New York Yankees and the Boston Red Sox. It's a rivalry that goes back to the early days of both teams and recently it took a very modern turn.
MLB investigators have determined that the Red Sox used Apple Watches as a form of sign stealing, which is when one team observes an opposing team's communication and uses that knowledge to their own benefit. Here's what happened, according to the New York Times.
"The Yankees, who had long been suspicious of the Red Sox stealing catchers' signs in Fenway Park, contended the video showed a member of the Red Sox training staff looking at his Apple Watch in the dugout and then relaying a message to players, who may have then been able to use the information to know the type of pitch that was going to be thrown, according to the people familiar with the case."