I have Mona, IceCubes, and Ivory installed on my iPhone. I primarily use Mona because it has the features I find useful (and I love creating themes). Ivory is nice for passive scrolling but is still missing a ton of features that I find necessary for using Reddit. IceCubes has a surprisingly nice UI, a couple of things even Mona doesn’t have, and is open source.
IMO, these three apps are the best for Mastodon on ios. I also want to support the developers.