On a phone, a manga page and a casino screen compete for the same scarce space:...

https://www.beacon-bookmarks.win/what-makes-a-manga-page-easy-to-follow-on-a-phone-the-same-design-choices-help

On a phone, a manga page and a casino screen compete for the same scarce space: your attention. Strong focal points guide the eye, readable controls prevent squinting, and smart contrast keeps details clear without clutter