The premise, like that of most major leaps for humanity, is simple: Participating McDonald's locations and other users mark whether the restaurant's ice cream machine is operational within the app. You'll then see a pink cone (good to go) or a gray cone (really really bad) on a map that'll even give you turn-by-turn directions right to the sugary brain freeze.
If you're going to download the app, act like a good citizen and "flip the switch" to let the world know whether your local machine is operational. As the product description says, "Our community-based system relies on your contributions to the database: so if you see something, say something!"
This act of public service was created by Raina McLeod, who told BuzzFeed, "I came up with the idea for the app around a year ago, after a late night Oreo McFlurry craving went unfulfilled due to the ice cream machine being down."
Thank all that's good in this world that she decided to act: We're all better off for it.