You may have noticed that the forum look just changed. A lot of new features just went in, and the layout hasn't been touched. We know it's ugly… that will change. But it has more features now.
Are you using the new Lightroom; the version that's the same (mostly) on desktop and mobile? Then you may have noticed that a few features are NOT actually on both platforms. The ones that get me the most are Copy Photos (ie duplicate photos) and Batch Paste. I've found a way around it… in a round about sort of way. Check it out!