Did you score a coveted reservation at the latest restaurant opened by a "Top Chef" winner? Show it off, and rub it in your online community's virtual faces by checking in with the free FourSquare app for Android.
Before Facebook had places, hundreds of thousands of app users were checking in to the location-based app, FourSquare, which lets you integrate check-ins with your Facebook and Twitter statuses. Basically, you compete with other users to become the mayor of popular public spaces, like Starbuck's and Whole Foods Market, and some not-so-popular private spaces, like your personal couch or your therapist's office, by visiting the most times in any given period.
The best FourSquare mayorships offer deals. For instance, I became the mayor of my neighborhood salon for a brief period and earned a free massage! Some places, like Chili's restaurants, even offer incentives like free chips and salsa for just checking in, and showing your server that you did so.
You can also earn badges for checking in to a series of different venues or for other random accomplishments like checking in to a place where thousands of people are already checked in.
Another handy use for FourSquare is the ability to leave advice about venues. When you check in to a place close to somewhere one of your friends has left advice, the information will pop up for your consideration. Or, you can just use it to stalk people and invite yourself to friend's intimate dinner parties.