Slack is an application that helps teams communicate and work together by combining messaging, file sharing, and app integrations in one place. It makes it easy for teams to stay connected and work efficiently, whether they are in the office or working remotely.

Basecamp, formerly named 37signals, is a privately held American web application company based in Chicago, Illinois.

Trello is a web-based Kanban-style list-making application. Originally made by Fog Creek Software in 2011, it was spun out to form the basis of a separate company in 2014 and later sold to Atlassian in January 2017.