I've heard there's an official kbin app in very early stages. I don't know who's working on that, but it's not in the 2023 roadmap that Ernest has shared in the sidebar - and it rightfully doesn't need to be a main focus at this early stage. I know most people reading this have probably just gotten here as well, but I wouldn't be surprised if a developer out there has already started. The PWA (web app) experience isn't bad on mobile. It's no native app though. Lemmy has that going for it, and I'd love for that experience here on kbin.
There is no publicly available API for kbin yet, though it's intended. Once the lead developer has breathing room I'm sure that's still on the to-do list.
API discussion was definitely the catalyst. But the doubling down and response of the admins to the community was what finally sealed it. Hopefully the mass exodus of users to federated servers makes the news cycle too. When communities reopen in a few days then I think there will be a lot more awareness raised for them and there'll be another wave. We won't get to Reddit's 15mil or whatever active users in a week but the fact that we could be even 5~10% of that is insane.