I have definitely had the "the thing I was looking at right after the app opened disappeared after a few seconds and I can't find it again" experience /u/mfontani describes.
Great for the web team if they are doing a better job than the mobile team I guess.
I also see if it the app is running in the background and I switch back over to IG. I can be in the middle of my feed and scrolling and after a few seconds it refreshes and I lose my spot.