Designing a full-sized game for a five-inch screen means focusing on...

https://sizedesk.com/what-happens-when-a-full-sized-game-has-to-fit-on-a-five-inch-screen/

Designing a full-sized game for a five-inch screen means focusing on priorities, not just shrinking everything down. You start with touch-first controls that feel natural on a small display. Then you decide portrait or landscape works best for your game