We are both interested in making an app that has no real purpose. We want it to look cool, and to tap in to as much passive data collection as possible because we both are quantified selves. So we are taking our inspiration from Nicholas Feltron and his annual reports.
So the basic idea is that users will download an app, and then input information on their various social media outlets (FB, Twitter, Instagram, etc.) and then let the phone start grabbing all that information and begin a data visualization on the website that will show that info in a visually striking way.