I've not used either, but reading their forking announcement (https://blog.gitea.io/2016/12/welcome-to-gitea/ https://blog.gitea.io/2016/12/welcome-to-gitea/),

I've not used either, but reading their forking announcement (https://blog.gitea.io/2016/12/welcome-to-gitea/ https://blog.gitea.io/2016/12/welcome-to-gitea/), it seems the main difference is that Gogs is maintained by a single person and Gitea by a team of people. The comments on that post suggest that Gitea is more actively developed, at least shortly after the fork, but I haven't checked to see if that's still the case.