jointhefediverse.net seems to be a commonly linked resource for directing people to join the Fediverse.
Curiously, it does not list Lemmy under the list of Reddit alternatives. Their GitHub README explains why.
Previous relevant discussion: https://lemmy.ml/post/78808
I would sort of consider web as the other one, since kbin (and now mbin) were designed to play nice with mobile browsers, I use mbin on my phone via PWA and I’m pretty happy with it, aside from mbin UI issues which I keep kicking around the idea of fixing but have been lazy about it.
I see, I usually use PWA myself, but I’ve heard quite a few people saying that apps were a deal breaker for them