To rule on whether Apple has a monopoly, the judge will have to first decide how to look at the market in this case. Epic argues the “market” should be defined narrowly, and the judge should only consider the Apple mobile operating system. That’s because, Epic argues, it’s the only distributor of apps to smartphones around the world, and it also wields power over the payments system. But Apple has argued the market is much broader. If the market is defined as smartphones, it would include the many U.S. phones running Google’s Android operating system. And the iPhone maker argues the judge should also consider the many other platforms people can play Fortnite on, including PCs, gaming consoles and more.