I don't see any practical difference between whatsapp and imessage. iphone has so many apis such as callkit that make apps that use them feel like first parties

I don't see any practical difference between whatsapp and imessage. iphone has so many apis such as callkit that make apps that use them feel like first parties. I think the only real difference is that you can use the built-in messages to read and send sms... which nobody uses anymore.