While trying it out, I discovered that the Wikimedia Commons app includes the same functionality, so I decided to see how it works.
Opening the app for the first time, and giving it permission to access my current location, it shows me nearby Wikimedia Commons entries that are missing an image:
Tapping on the nearest icon, I see that it’s the Honourable George Coles Building, just half a block from my house:
Tapping the “+” icon, I can take a photo, and then, after confirming I want to upload it, I can add some metadata:
Clicking “send” uploads the image to Wikimedia Commons where, indeed, it sits there waiting to be used.
What I realized after uploading four images is that all the app does is to facilitate the upload; it doesn’t actually associate the images with the place it originally identified, it simply geotags them and makes them available for further use in the Wikipedia universe.
So, taking things forward, I created a Wikimedia Commons category called Honourable George Coles Building (Charlottetown) and, using the All Souls’ Chapel category as a template, I fleshed out the metadata.
Next, I edited the Wikidata entry that got me started, clicked “Add Statement” and added the images I’d just uploaded.
Finally, I edited the List of historic places in Charlottetown page in Wikipedia and added a thumbnail image and a link to the Wikimedia Commons category page.
Now that I’ve been through this once, the next time around should be all that much easier; and there’s a good collection of “missing image” markers nearby in the Wikimedia Commons app to keep me going.