Did I post over here about the battle of the DMs yet? It seems I haven't... https://robla.blog/2020/07/29/battle-of-the-dms/
@robla Signal is my primary communication method with my immediate family and most of my friends, but it's taken a while to get everyone on board. Now that it has stickers and reactions, I don't think there's any reason not to use it.
WhatsApp, IRC and Messenger are secondary.
@robla commented on FB already, but Mastodon/Tusky (for android) actually works out pretty well for me, theoretically. But yeah, no one is here (ohai good friends, I mean no one I normally DM/chat with to coordinate in my day-to-day). :(
@robla It depends on where I interact with people most; usually I'll just use whatever feature is most closely associated with that. (I like using IRC for DMs but that doesn't work for most people I interact with.) For people I mostly interact with offline, either email or Signal.
Server run by the main developers of the project 
It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!
2/ What I'm looking for is what do people prefer to use for DMing? Do y'all prefer Mastodon, or does that only work for some of your friends and family?