Playing a browser game on your phone can feel just like a native app because it...

https://www.acid-bookmarks.win/mobile-browser-games-can-feel-native-because-they-support-portrait-mode-making

Playing a browser game on your phone can feel just like a native app because it loads quickly and remembers your progress through caching. The game works smoothly in portrait mode and uses touch-friendly controls designed for easy tapping and swiping