Designing a full-sized game for a five-inch screen is all about focusing on...

https://wiki-square.win/index.php/How_Do_You_Test_Mobile_Game_UI_for_Thumb_Reach%3F

Designing a full-sized game for a five-inch screen is all about focusing on what matters most. You can’t just shrink everything down. Instead, prioritize touch-first controls that feel natural on a small display