https://de.wikipedia.org/api/rest_v1/page/mobile-sections/Watkin%E2%80%99s_Tower provides the following geo coordinates:

"geo": {
  "latitude": 51.555556,
  "longitude": -0.279444
},

The Koordinaten link from de:Watkin's Tower shows the same coordinates to me:

Geo URI	geo:51.555556,-0.279444

Edit: Ok, just realized that this is not about the geo portion missing but having the wrong location in there. Updated the comment to reflect that.

Duh, the coordinates I was talking about don't even get used by the app. This is about a marker in an image in the infobox.

Looks like an issue with Template:Location map in Parsoid. VE has problems with this template, too (T52714).

Supporting the location map feature would be an unreasonable amount of effort for a legacy feature that has now been replaced by proper software support for maps. Other software components don't support them either, see e.g. T193822: Pushpin disappears after opening image in mediaviewer or T64572: Media Viewer and location map overlays. I would suggest declining and pointing people to Maps (Kartographer) as a replacement for the template.

Report from OTRS - https://ticket.wikimedia.org/otrs/index.pl?Action=AgentTicketZoom;TicketID=11258527

Report from the OTRS: https://ticket.wikimedia.org/otrs/index.pl?Action=AgentTicketZoom;TicketID=11257801#Article13477096

From Android email:

Call "Land (Deutschland)". Have a look at the map. Try different devices and turn them to landscape/portrait.

Thats the problem with all those maps. Try "St. Helena (Island)". The difference can bee about 2000km, depending on the device/sreen.

+1 user through the Android support email:

The map was marked incorrectly in the Qing Dynasty and Beiyang governments. The incorrectly marked places were marked in red.

+1 user through the Android support email:

Beiyang Government or Beijing Government It is not a map from In 1924, the Mongolian People's Republic was established. And exclude the Republic of Tuva, parts of Central Asia, Afghanistan, and Bhutan.

+1:

The map of Bohai is wrong. It completely occupied Liaodong (the place marked with a red circle) and it was also Bohai territory.

+1:
Daegu Metropolitan City was incorporated into Gunwi-gun.

There is an issue with the Vorlage:Infobox_Verwaltungseinheit_in_Deutschland template on German Wikipedia, visible among others on
https://de.wikipedia.org/api/rest_v1/page/mobile-html/M%C3%BCnchen (compare to the position of the dot on https://de.wikipedia.org/wiki/M%C3%BCnchen) and https://de.wikipedia.org/api/rest_v1/page/mobile-html/Helgoland (compare to https://de.wikipedia.org/wiki/Helgoland).

A priori, the issue comes from the fact that the red dot is shown relatively to the table cell rather than the map itself (to be confirmed), and that these do not have the same width on the PCS rendering than on the desktop rendering. Why exactly that is the case may warrant a look, but it seems to me that the position of the dot should not be dependent on that (from a template design point of view). It's also quite unclear to me if the issue also triggers on mobile-web, where the responsive design seem keep the infobox width more-or-less stable.

Additionally, some issues reported on this ticket have 0 information on the impacted page (or even wiki); some others (such as https://de.wikipedia.org/api/rest_v1/page/mobile-html/Watkin%E2%80%99s_Tower) have apparently been fixed by template/module edit.

I'll have a last look at the table width considerations, but a priori the fix is on the template rather than on the code base.