Well, since it's a web client, it's pretty easy to just try it out, but the benefit of Phanpy is not that it's a web client. It's just it has a lot of nice little UI touches that make it very pleasant to use. There's an overview at [1], but I'm not sure if that does it justice - you kind of have to experience it. The most noticeable is that all boosts are grouped in a horizontal carousel, whereas you vertically scroll through other posts, but I can't quite explain why that's no nice.
[1] https://github.com/cheeaun/phanpy?tab=readme-ov-file#design-...