There is only Jerboa (with Lemmur being broken and abandoned). But you can install the PWA webapp in your mobile browser and that works quite well. Not sure if Lemmy supports web-push already though.
Thanks! Someone shared the TestFlight link here in a comment response, and I was able to get it installed. Brings back memories of when I used to have an iPhone app people used, and I used TestFlight for testing when it first came out. Ahh, good times.
Anyway, from what I can see so far, mlem looks really, really good, and has a lot of promise.