Why people share less on mobile
At Moovweb, we power over 250 mobile experiences. Many of our customers are in the eCommerce space. We studied a subsection of our customers' data and discovered mobile sharing buttons aren’t getting much use: Only0.2% of users ever click on a mobile sharing button. Mobile users click the sharing buttons 35% less often than they do on the desktop.
I've linked to this article before, as I think they're asking the wrong question, but I do think lower share rates on mobile are to be expected.
The trouble with sharing on mobile is most people use native apps for their social accounts on mobile devices. Click a share link in a mobile browser and because you aren't logged-in in the browser, it's not worth the hassle. The answer would be for share buttons to open up the relevant native app.