- my mixed sport team has a group page, where we discuss the next game time, who can make it, etc. We don't need to Friend each other, or sign up to another service. We all have FB, so we just add/remove people very easily. Helps organise and track conversations easily. A new post each week, and everyone just comments on that. - my sister and brother live in other states of Australia. FB helps me see what they're up to (photos, videos especially). I call them regularly, so FB is just value-add.
- I have a young (under 2) son, and keep most photos off him off FB. However, occasionally (once every 2-3 months) we will share something so people in our wider network can get an update. It's not for us, it's for them. - I have a lot of friends I met through a time in my life (university exchange overseas, growing up, living in different cities). FB is a very casual, easy way to stay in touch. The barrier to entry is very low (literally, just click the 'like' button on their post).
- FB messenger: I use this a LOT. I also use SMS (via Signal), Hangouts and WhatsApp. Yes, they overlap considerably, but FB Messenger has the functionality, and critically the contacts, I need. Lots of group chats about different things (social events, family, etc.) and things like location sharing when I'm on my way home from work.
I don't endlessly scroll through updates on my feed page, and I don't get my news from FB. If I read the feed page (with the updates from friends, etc.), about 50% of content is secondary (meaning someone has shared a viral video, or something) and the other 50% is original content (holiday photos, though of the day, etc.).
Can all of the above be done on systems other than FB, yes. Do other systems have the low barrier to entry now that all of my friends are on FB, no.
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