From 2,997 active users across all lemmy instances at the beginning of June, the number increased to 52,797 by June 30th. Source.
An active user on Lemmy is "someone who has posted or commented on our instance or community within the last given time frame.โ Source. That means lurkers are not counted as active users. There are currently almost 200k total users spread across the top 10 non-bot lemmy instances.
We're really building something here!
EDIT: Looking for a lemmy app? Here's a whole list: https://lemmy.world/post/465785
That's what I'm using here. It has a few bugs (I can't turn off swipe gestures, and pull down to refresh never works), but it's minimal, to the point, and easy on the eyes. I think Boost for Lemmy has a good shot at being the popular client when it's ready, but for now, Connect seems to be stable on my device. I do like the web desktop UI.
I can't be too critical though because the whole community and user base is so young. If the Lemmy.world stats are any indication, the app userbase must be exploding too, testing paths that just haven't been tested much before.