Facebook Messenger, SMS and iMessage →
https://marco.org/2011/08/10/ben-brooks-facebook-messenger-sms-and-imessage
Ben Brooks:
That kind of seamless integration is how you push through change, not with standalone apps. Facebook Messenger may succeed, but it’s not going to hurt iMessage.
This is the smartest take I’ve seen on Facebook Messenger so far.
iMessage is truly transparent: less-observant iOS owners won’t even realize that they’re using it. Their SMS bills will just start to decline next month. It’s beautiful, really.