Correct but in Facebook’s case they were also trying to push Messenger as a messaging platform that you could use without Facebook too, hence a separate app mad

Correct but in Facebook’s case they were also trying to push Messenger as a messaging platform that you could use without Facebook too, hence a separate app made more sense on a technical level, but also it was a huge marketing move. I personally find it annoying that Messenger is integrated into Facebook enough that I’m notified when there are pending messages, but not enough that I can’t check my messages on FB app...