On Android phones. iPhone doesn’t have this privacy deficiency.
On iOS an app developer will need to register in advance which external applications their app intends to query, and the list needs to be very short and motivated. [1]
Incidentally, “I have a friend who says...” isn’t really a good citation anywhere outside Reddit - which HN resembles more and more each day.
[1] https://www.hackingwithswift.com/example-code/system/how-to-...
I suppose a more appropriate term of phrase would've been "I'd heard anecdotally...", but I agree I was lazy with my original reply. I appreciate the feedback.