Apps with 'ActivityPub-Servers' feature

Holos is a Fediverse client that turns your smartphone into a complete ActivityPub server. Unlike traditional clients that connect to remote instances, Holos runs the server directly on your device.

fediverse.party provides a guide for the fediverse, a interconnected network of servers each running a different platform for web publishing (i.e. social networking, microblogging, blogging, or websites).

A simple, minimalistic ActivityPub server written in portable C.

Epicyon is a fediverse server suitable for self-hosting a small number of accounts on low power systems.