It's made by the main Lemmy developer, but it's his personal project and not the official Lemmy android client. He's been making some controversial commits on Jerboa in the past on the basis that it's his personal project, so he can do as he please (unlike Lemmy which is funded by a foundation).
I like Flutter based apps, so that makes me happy. I saw it a couple of days ago and while it is lacking in features, it does feel nice to use and looks much better than Jerboa IMO.
Didn't work great when I tried it on Sunday. It would load my instance, but login was broken. Seems to be a bit better now. Weirdly my OP shows up in it, but your reply doesn't.