This is a really cool feature added by LeetCode. I like that they're using the following/follower system to introduce more social features.

But instead of "Friends check-in", I think something like "Following check-in" would be more useful.

Instead of only showing the check-ins/streaks of friends, it could show the progress of accounts we're following too. Right now, if I follow someone and they don't follow me back, I can't see their progress here.

But the reason I followed them in the first place was because I wanted to track their progress, not necessarily because they're my friend.

I hope you'll give it a thought. Thanks!