I think the new version of DTTG removed DT from the iOS share sheet. I usually save a few bookmarks during my morning news skimming, and today I can’t. 
You should see an entry marked DEVONthink in the Share menu.
I rebooted my iphone and it came back. Beats me.
A reboot is often a useful early tool in troubleshooting odd behaviors on Mac or mobile.
Yeh. For many years it was my first step. But things have gotten so reliable I just don’t think about it. I honestly can’t remember the last time I restarted my iPhone. My Macs don’t usually get restarted until I do my monthly maintenance — if I do it. I guess this is all good stuff 
We still advocate rebooting devices once a week or so.
Same here, DEVONthink share sheet simply disappeared. Glad to know it’s not just me!
Update: btw, restarting fixed it for me too.
Same thing happened to me. Also lost the Drafts share sheet. Rebooting my iPad fixed both.