(It's not showing up now. Were you guys testing something on your end?)
For the first time today, I saw a blue banner across the top of the question feed that said "2 questions with new activity" (paraphrasing, can't remember the exact wording). To the right of it was a refresh button (two circular arrows pointing at each other).
Clicking the refresh button seems to do nothing though. It didn't cause any noticeable changes to the feed, or give any feedback that it had even registered the press (like making the refresh button look pressed). Nothing new was loaded, or changed.
The banner also only seems to show up on Meta feeds. I have yet to see it happen in the SO question feed.
And yes, this was definitely in the app. I only ever use the Android app.
App version 1.0.95
Android 6.0.1; rooted.