Hacker News Reader

Yup, just right in the upper half of the page there is a big search box and an "sort by" popup button.

The main page has the search box & sort by: https://www.macsourceports.com/

I don’t see that on mobile. Just a list of games and a pager at the bottom that goes on for miles…

Yeah, I don't know why I've never added that, but you can filter games on the main page not the /games page.