Visual Studio Team Services - Visual Studio Team Services (VSTS) provides unlimited Git hosting, cloud build for CI, agile planning and continuous delivery.
Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
Helix ALM - Helix ALM is the single, integrated application that lets you centralize and manage requirements, test cases, issues, and other development artifacts and their relationships.
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.
codeBeamer ALM - Integrated application lifecycle management (ALM) platform
Slack - A messaging app for teams who see through the Earth!