I always prefer first party app over third parties (Dropbox, Google drive etc). But seriously, today I got two PDFs in an email and I just needed some place to put it, before uploading it to a website. Well guess what shows up in the share sheet when I press the up arrow? Dropbox, Google drive, Documents, Notability, OneNote etc etc. Everything except iCloud Drive. Seriously why? I have the iCloud Drive app enabled on my iPad. But I don't even understand how to use it. Can someone shed some light?