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I do use WhatsApp for more direct communication. The biggest benefit of that one is the security. If Hive offered a similar app (which I believe would require a smart contract to ensure that the content of conversations is not posted on the chain), I'd be ok with using it too.

I believe Hive already has a private messaging app. Forgot the link though.

There's a public messaging app on PeakD, if you're interested in Discord-like app.

I did actually see that one, but it never seemed to work for me.

Haven't heard of the private one! That would be interesting to see.