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

https://wiki-planet.win/index.php/How_Do_You_Design_for_Both_Tablets_and_Phones_Without_Breaking_UI%3F

Designing a full-sized game for a five-inch screen is all about smart priorities, not just shrinking everything down. It means focusing on touch-first controls that feel natural on a small screen