A brand new Google app for your iPhone, currently available on an invite-only basis in the App Store, wants to take the pain out of finding people who are free to hang out.
Aptly named Who’s Down, the 16.2-megabyte download comes with an easy to use user interface featuring a slider that, when toggled, tells the app to let others know you're down to meet up, allowing you to see which of your friends are free to hang out.