One scoreboard, two ways to play: track a game on the spot, or sync it to everyone's account as you go.
Set up players and pass one device around the board. 501, 301 or a custom start, with averages and checkout suggestions built in.
Pick your players from friends or groups and play on one device, same as offline. The difference is everyone's stats and the result sync straight to their account, and feed the shared leaderboard.