For the same types of reason phone manufacturers find phone, email, and messaging apps to be logically separate even if they are all essentially related.Well about the only time I message someone on Facebook is when I am reminded of that person by something I've seen on Facebook. I don't reply to someone who calls, texts, or emails me with a Facebook message.
Facebook can do whatever the heck they want, but so can I, and if they fragment their app and make it hard to use like Foursquare did, I can walk away. I just don't understand why they think we'd find separate apps more useful. Why wouldn't they want it to parallel their website organization?
Facebook sees their messaging service as more than just a small thing related to their main service they see it as a bigger item that's related but not depended on the rest of the newsfeed service Facebook provides. The way you use it is one thing, and maybe many use it in a similar fashion, but many more still use it similar to how they use a messaging service like iMessage or WhatsApp and often want to message people without the need or care for newsfeed updates. Facebook wants to promote that but it's not aimed at everyone. Since you barely use the service anyway (as most who have mentioned displeasure with this in threads like this) it's not something aimed at you nor will Facebook really miss those who will decide to jump ship because of something essentially inconsequential like this (as those were barely on the ship at all if at all on it).
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Yup all that is totally happening in a parallel universe somewhere.Why would they deliberately hamstring their app? Especially now, when the youth are fleeing Facebook for no longer being cool.