Fedidb.org recommends people who view their statistics on their “Threadiverse” tracking page that people should not use graphs and numbers from the total users due to the surge of bot-accounts, and should instead use the monthly active users. This puts the “Threadiverse” at 87,089. Lemmy with 37,197 and Kbin at 44,136. Fedidb.org also shows that the number of accounts is now at 1,75 million, though most of these accounts are probably just bots.
I think that perhaps more Reddit users are moving to Kbin because it feels & looks more like Reddit. At least that is the feeling that I get. But in all honesty, no idea.
I’m on Lemmy via Jerboa because that was the first app I found for fediverse browsing on my mobile.
I seems more desktop/laptop users are partial to Kbin, but mobile users drift towards Lemmy from what Ive seen.
There are currently no Kbin apps because Kbin doesn’t have an API yet.