How does "Find My" application is working with location service changes in iOS 13 I have installed iOS 13 and gave it a shot to Find My application. First question is the location service and I have chosen "While Using App". But what does that really mean? Does it mean that I have to have Find My application running all the time so people can see where I am. I am a bit confused.
The While Using App permission means it's using your location when actively running (foreground) or in the background.

You can keep 'Find My' app in the background (do not force-quit) and it will be able to access your location.

Update: Source:

The Always Allow option, which grants an app “background” location access, has been removed from the initial location permissions prompt. 

Instead, users can select Keep Only While Using (aka “foreground” permission) or select a new option, Allow Once. 

So how does an app then get upgraded to “background” location permission? If the user continues to use the app, iOS 13 will now automatically and periodically prompt to upgrade location permissions from While Using to Always Allow.