Hi Dani -
Thanks for the reply. We were thinking this was likely an iOS restriction. I tried the workaround with some success (such a hassle, but at least it works). But, like you, I can't see the "Open in" when using the gallery.
I am doubting that iOS restriction will be going away any time soon. Obviously, students can upload files from their computers, so this isn't a huge deal-breaker at all. Just a bummer. I'll be following the open issue to keep track of where you guys are at.
Thanks so much!