Foursquare's dedicated check-in app, Swarm, has been adding missing features ever since the startup split the main mobile app's functionality into dedicated place discovery and check-in apps.
The new Swarm 3.0 for iOS, which released earlier this morning, brings back leaderboards after gaining mayorships early in the summer. In addition, messages and notifications have been unified under a single inbox view.
Your worldwide and nearby views are now folded into a single Friends tab and a revamped Here Now section is now located under the Nearby section.