As the OP, it's like the others say, Apple is bigger in the US. But also, you can still message Android users because it seamlessly switches over to SMS.
This of course makes it usually more expensive for the Android user to respond. But due to the level of iMessage use they don't have an alternatives. And most plans are now quite generous with SMS bundles anyway.
the blue bubble is iMessage the green one that always slowly receive messages and no typing indicator, images, videos , gifs, payments thats your rare android friend :)
Because I already have a perfectly serviceable message app that comes with the phone by default. Do the three in your list interoperate with each other, is that why you're suggesting them?
Because it’s a lowest common denominator, of sorts. Also, none of those apps are able to handle SMS on iOS. Also, why not use iMessage vs all the other ones you mentioned? Different strokes for different folks.
What's interesting here is that it's only the US where Apple has the dominance. Everywhere else in the world it's mostly Android in the mobile phones.
Edit: What I mean with this comment is that HN has lots of readers outside of the US. Here using only iMessage would be a bit weird, and for that reason everybody uses either Signal or WhatsApp.
Huh, i replaced europe with usa in the url and it gave me different figures than when you click the united states link. Still 50% isn't enough to warrant using iMessage. Especially the way we use chat apps these days.