Foursquare is a pretty popular app particularly because it’s cross platform and already available for the iPhone and Android. It gives you a bunch of ways to stay in contact with your friends. When you get to a meeting place, for example, you can ‘check-in’ so your friends know you are there and you can then find out other places in the area. And when you get to a location you can find out tips from other Foursquare users (like to avoid the clam bake on Sundays). It sort of seems like a mix between Twitter and Google Lattitude. Anyway, more info on Foursquare can be found here. To get the beta for WM you’ll need to email the developer or complete a webform. The details for WM are located here. As a beta it has some limitations (listed here) and currently uses Goog locations and not GPS, doesn’t support push notifications and doesn’t tell you where your friends are. If you’re into Foursquare it’s a start so check it out.