I use a browser even on mobile. Never found an app that does anything but mung HN up more.
I tend to bounce between the main page and the new page. Morning: Scan the main page...read the good bits. Jump to new. After Lunch: Scan the main page jump to new.
Basically a couple times a day I Do the main page then browse new entries.
As for the chrome extensions. I find they all seem to make HN slower. And it's slow to begin with a lot of the time.