The Swims tab is where you can see your recent activity, as well as that of anyone you are following. There are two screens: "only me" and "following".

You will see your own recent activity on the left default screen. If you are following other people, you can toggle to the right screen to see their activity combined with your own.

Each activity will show you a graph. If you tap on a specific activity, you can see further details about the swim. You can find information on analyzing your pool, open water or swim spa swim in the relevant articles.

Below the information about the activity, you can "like" the activity or leave a comment, as well as see how many "likes" and comments are already attached to the activity. You can also share your swim or export the swim data for your swim. 

Clicking "view all" shows all "likes" and comments on the activity.