To everybody freaking out: It's a todo list, that stores your info in your dropbox rather than the sites database[1]. Brilliant idea, terrible execution.
If I was the person that developed this, I would have spent <$25 on themeforest.net and tossed up a simple splash page with a call-to-action button and a short description of what it does. No one in their right mind is going to blindly hook up their dropbox to a blank site.