iOS 9.3.1: Dropbox 6.2 doesn't appear in Activities in Photos From the Photos app in iOS 9.3.1, Dropbox does not appear in the list of places where I can share photos.

I've tried clicking on the three dots at the right of both activities bars, and Dropbox is not an option in either list.  The various guides I Googled all suggested that if I had the latest version of Dropbox installed, it should show up in this list.

I've looked at the settings within the Dropbox app, and I've also looked at the Dropbox settings from the iOS settings app, and in neither place did I see any kind of switch to enable it to appear as an activity.  

Any ideas?  This is driving me mad.  Thanks!
Go into Settings > Dropbox and verify photos is turned on. Now go into Photos, select a picture and tap the share icon. There are two rows of icons, you want the lower row (on mine it starts with "Copy.") Scroll the icons to the left side of the screen



If Dropbox is not there tap the "..." "More" button and turn on Dropbox.

That's how it worked on my iPhone 6+ with IOS 9.3.1.