Bluesky

Bluesky is a social networking service operated as a Public Benefit Corporation and built on an open protocol, the AT Protocol. The service is available through a web application and mobile apps distributed via the Apple App Store and Google Play Store, and the company states it serves millions of users. Its stated premise is that social media should not be controlled by a small number of corporations, and it positions itself as building an open foundation for what it calls the "social internet," including a commitment that the social network cannot be bought by a single individual or organization.

Product features emphasize user control over the experience: multiple selectable feeds, including chronological and algorithmic options, plus moderation lists and content filters that let users determine what appears in their timeline. The company says future development will let people and organizations use open tools to contribute more directly to moderation. A single Bluesky account provides both access to the social network and a shared identity usable across other applications on the same open network.

Alongside the consumer app, Bluesky maintains open-source infrastructure and public APIs for third-party developers, including a public firehose of messages and events, tooling for custom feeds and algorithms, an "Auth with Bluesky" sign-in mechanism, developer documentation, and public GitHub discussions. Third-party projects built on the protocol that Bluesky highlights include Graze (custom feeds), Tangled (a social git platform), Skylight (portable content and followers across atproto platforms), Leaflet.pub (collaborative documents and blogs), Streamplace (open-source video streaming for decentralized social networks) and Germ Network (an encrypted messenger with AT Protocol integration).