Groups.io is described as 'A modern platform for online communities. Powerful management tools. Mobile ready. Free and paid plans. No ads, no tracking' and is a team collaboration tool in the office & productivity category. There are six alternatives to Groups.io, not only websites but also apps for a variety of platforms, including Android, iPhone, Android Tablet and iPad apps. The best Groups.io alternative is Basecamp. It's not free, so if you're looking for a free alternative, you could try Google Groups or winio. Other great sites and apps similar to Groups.io are Gaggle Mail, FreeLists and XS usenet.