Either/Or actually. So for example my workflow might be to import my photos to desktop and edit the photos there, creating a new collection which I then Sync with Lightroom Mobile. I then want to export the whole collection to camera roll so that I can grab the edited photos on my mobile devices and share from there. But I can only select 5 photos at a time and click "share" on mobile, then select save to camera roll. So when I have 100 photos in a collection, this gets very tedious. I am unable to find a way to do it on desktop version either that is simple one click (I've seen long complicated workarounds, but that's just silly it seems).
Thank you sarsaxen!