One year on from its launch, the App.net social network has announced a $2.5m funding round from VC firm Andreessen Horowitz as it continues to build its own social graph for other developers to build apps on. “Why did we choose to raise this money? We are just starting to realize the potential of what App.net can be, and we want our developer and member community to be confident that App.net is on strong financial ground and here to stay,” blogs CEO Dalton Caldwell. “This financing gives us an additional cushion and resources to manage and support the infrastructure and staff that run App.net.” It remains ad-free, but it’s become more than just a me-too-but-paid Twitter microblogging service. Developers have been creating apps based on its platform for private messaging, file management, photo-sharing and other uses. Music? Not really a big factor yet.