This rings very true. I'm down using Facebook/Twitter for work, or checking every 2 or 3 days if I'm bored, desperate or looking for something in particular. Instagram is about a 50% mix of pretty things and friends, but the pretty things post way more often, so the split is heavily in that direction.

I'd say approximately a third of the friends I chat to regularly (late 30s ish) have left or don't use Facebook - but we're all in lots of WhatsApp groups. A couple with big groups of friends, but lots that are started before a night/day when the few in the group got together and just stay open to extend the fun from the day with relevant stuff.

It feels a lot more private to post to these. You can share things without some random friend commenting, or judging because you know exactly who you're sharing with. It feels more like having a pint with a couple of mates than pinning something to a noticeboard that friends, relatives and work colleagues may (or may not, depending on whether FB deems it worthy) seeing.

WhatsApp has definitely replaced Facebook for a few of us - and bearing in mind they have the same overlord, it seems like a pretty canny buy now.