I don’t really like Apple, but once in a while they do the right thing. This comes from the App store’s new labels on apps.
Signal just has “Contact info” under the “Data NOT linked to you” category. This is just the phone number + contact discovery.
UPDATE
There’s another post adding telegram here. This is what it looks like:
Good to see those in a position to comprehensively know these details sharing in an easily consumable format.
(What they probably won’t show you as that just about every action on an iphone generates a phone-home event—as viewed through proxy logs)
This type of graphic might make a good standard for others to follow (looking at you alphabet google android)