Substr is described as 'Community layer built around Nostr. It gives threads a shared home, so conversations feel easier to follow than they do in one endless feed' and is a Social Network in the social & communications category. There are three alternatives to Substr, not only websites but also apps for a variety of platforms, including Android, iPhone, Android Tablet and iPad apps. The best Substr alternative is Lemmy, which is both free and Open Source. Other great sites and apps similar to Substr are Reddit and Slashdot.
Lemmy is similar to sites like Reddit, Lobste.rs, or Hacker News: you subscribe to forums you're interested in, post links and discussions, then vote, and comment on them. Behind the scenes, it is very different; anyone can easily run a server, and all these servers are...
An extensive platform for user-shared content and discussions, organized into niche 'subreddits' across numerous interests like news and video games, with a dynamic voting system influencing what appears on the front page.
News for nerds, stuff that matters. Slashdot (aka /.) is a technology-related news and discussion site with a focus on Linux, free and open source software and information freedom and privacy issues. The software it runs on, called Slashcode, is open source.
United States