You make a note, they are designed to look as good as any social media posts.
You can share the note with whomever you wish, using what ever messaging system you you like, and the note will look as good as a social media post, ie how you designed the note. I am sorry, it does take a bit of imagination. I never wanted to pitch it as a social media app, but, its as close to personally controlled social sharing that I could conceive.
You dont have to pay to use it. Very few people need to use cross device sync and those who do seem happy to pay for it.
Ie, it is free, so if any ones wants to try it, I would love to hear.