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

https://stateofseo.com/how-do-you-test-mobile-game-ui-for-thumb-reach/

Designing a full-sized game for a five-inch screen is all about smart priorities, not just shrinking everything down. You focus on touch-first controls that feel natural in small hands and decide if portrait or landscape works best for the gameplay