It would be good to have a good maintenance and next development story if you go with the bounty direction. My guess would be that the mobile app would eventually have higher usage than desktop.
Just to brainstorm what I think would be great set of features:
Main list
  • Be able to swipe on single post to either tip it with sats or to save it for later
  • Be able to swipe from the side to see menu different substacks, etc. and with my wallet and notifications
  • Maybe even have bottom bar with "posts", "notifications" and other custom tabs
Post Detail
  • It would be great if it would have 2 tabs and I could swipe left - right easily between the article (e.g. iframe the actual page) and the comments section
  • On phone there are more times when it's appropriate to show a dialog or a detail box, e.g. when clicking on someone's name.
Integrations
  • The app should create an item in my "Share" list, so when I'm e.g. browsing something on twitter, I can click on "share" and it gives me option Stacker News
  • The app itself should have a share button so I can share SN post somewhere
  • It could more seamlessly integrate with other Lightning Wallets on your phone, like stacking directly into the wallet :)
Just for inspiration, I really enjoy and still use "Materialistic HN" (github), but I think the app is no longer in play store.