The Apple App Store has begun to allow Game Streaming Services such as Xbox Cloud Gaming which were previously only available via web browser.
Game Streaming Services allow users to play games on their mobile devices by remotely accessing a beefier computer. The game is displayed on the phone but the graphics are all processed by an actual machine instead of on the mobile device itself.
Streaming has become a popular way to play games on mobile devices as mobile data becomes more reliable and wi-fi signals become more commonplace in public spaces.
However streaming games has its own set of challenges including input lag. While input lag can basically kill the experience of many games, users on mobile devices consider it worth the tradeoff; unlike the ill-fated Google Stadia which tried to popularize streaming games on a home console.