Foursquare is a better Dodgeball, for those who remember the now-defunct social-networking, texting, friend-locating mobile-phone app. The new iteration, rapidly being installed on iPhones across the city, is a fast route to a good night out. Download the app free at playfoursquare.com to track your friends’ locations (meaning no more rounds of “Where are you?” texts). It’s also a game, with goofy badges awarded to users who check in frequently. And most helpful, members share their ample nightlife experience; according to one enthusiast, the saffron Sazerac at Apotheke is the drink to get.