Ad-Free Social Platform App.net Raises Another $2.5M From Andreessen Horowitz

App.net, the social platform created in response to the ad-driven consumer social networks (specifically Twitter), just announced that it has raised $2.5 million in new funding.

The announcement came as part of a longer blog post celebrating the project’s one-year anniversary. The post implies that Andreessen Horowitz was the sole investor in the new funding, and when I emailed founder and CEO Dalton Caldwell to check, he confirmed that’s the case.

The firm backed App.net’s previous iteration, photo-sharing app PicPlz. (You may remember all the discussion last year around the fact that Andreessen Horowitz placed its bet on PicPlz rather than its Instagram, where it was also an early investor. Or you may remember Caldwell’s eloquent response.)

The App.net project raised more than $500,000 through crowdfunding. Caldwell said this is the first time Andreessen Horowotiz has “written a check” for the company since then, but he added, “They have been incredibly supportive during every phase of the company.”

In the blog post, Caldwell writes:

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. This financing gives us an additional cushion and resources to manage and support the infrastructure and staff that run App.net. Our team, including our investors, are 100% committed to App.net’s services-based business model where our customers are our users, not advertisers.

The post also offers an update on the company’s progress. Again, the vision is to create something that users will actually pay for — not a social network, per se, but a real-time social platform that other apps can build on top of. And indeed, a number of apps have been built on the platform, including private messaging app Whisper and messaging/microblogging app Felix. There have been other additions and changes to the platform over the past year, including the launch of a free version.

“In year two, as our focus expands from simply trying to deliver basic ‘1.0’ versions of our API, our overall mission remains the same: building a social platform with better aligned incentives with both users and developers,” Caldwell writes.