TWUNCH IPHONE APP
Look at all the twunches registered on twunch.be. You can subscribe to them with your twitter account and get a detailed overview of the map and other subscribers.
If you want to build the app yourself, the only thing you'll have to do is add this twitter.plist file to your project, make sure to use your own twitter API keys.
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
App website can be found here.