It’s not that the smattering of fresh new companies presenting at the annual TechCrunch50 start-up launch conference was boring, per se. Most of them, in fact, had an extremely practical slant to them, like the array of job- and car-hunting sites that take something Craigslist does and make it way less sketchy. And therein lies the problem: Sometimes, those sorts of productivity and next-gen enterprise start-ups simply aren’t that cool and shiny when you stick them into a PowerPoint demo.

But it was on the morning of the second day of the conference that the judges, audience, and organizers seemed thoroughly impressed by an app that they could actually use. Meet Rock Solid (previously CitySourced), a new iPhone app that lets the residents of an individual city log complaints and inquiries–graffiti, potholes, neighbors who go streaking–and send them straight to City Hall.