Foursquare's newest app Swarm takes all the social features of Foursquare, adds a few more, and puts them all in their own standalone app. With the app, you can see where your friends go, create spur of the moment plans, and stay on top of your own Foursquare activity.
One of Swarm's biggest features helps you create a plan that you then share with your Foursquare friends to see if they want to be apart of it. You can create a vague plan about going to the beach, or add more specific details about the time and tag a Foursquare location, so your friends know where you're headed and when.
