FWIW, "talk" is what came to my mind.

But it's social media though, so the other yakking will be involved...

I've only ever seen that spelled as "yak", so it took me a while to make that connection.

I thought "yak" was the bison animal. And that's what I thought of when I saw the name of this app -- not vomiting.

That's "yak"

https://www.merriam-webster.com/dictionary/yak