How do I find out which app is using my location in the background?

There is a hollow location icon present at all times in my iPhone's status bar.

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How do I find out which app is causing this? There used to be a section called "Location Services" in Settings but I can't find it anymore. I'm running iOS 11.4.


Solution 1:

Location Services is under Privacy in Settings. You can scroll through the list to see apps which have used geofences to find the one relating to the icon showing it in use.