So you don't get any errors in the console, does the Safari browser display any information? I have previously seen a small message at the top like; "A problem occurred with this web page so it was reloaded", is this something you have seen?
I would guess that it could be related to memory usage in that case.
By "edit my atlas" do you mean that you have changed the texture profiles to have a maximum size for iOS, or did you just remove images from the atlas so it resulted in a smaller atlas?
I suggest that you try to create (if you haven't already) and tweak your texture profiles by setting the maximum texture size in steps and see if you can hit a sweet spot where it works.