After using it a bit I have this to suggest:
1) "Next page bar" behavior.
When scrolling through threads, the "next page" bar shows up at the bottom.
I find it slightly annoying as it blocks the text under it and it's easy to tap "next" when I'm scrolling recklessly.
My suggestion is to make the "next page bar" only appear when the screen is tapped or double tapped and when you reach the bottom of the page - not when you're scrolling through a thread.
2) Zoomable pictures.
Being able to tap on a pic and bring up a full screen view of the pic. Similar to the default "Photos" app.
3) Post previews.
I typically format my posts so they're easy on the eyes and being able to preview and make changes before I finalize the post makes that easy to do.
Since I do most of my forum browsing from my phone, this app is awesome! Great work so far.