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.
TestRail - TestRail provides comprehensive test case management for software testing. Organize your testing, boost productivity, get real-time insights, and track progress toward milestones. Integrates with leading issue tracking and test automation tools.
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.
PractiTest - PractiTest is a cloud based Innovative test management tool.
Slack - A messaging app for teams who see through the Earth!
Qase - Test case management software for QA and development teams that helps you make your product better.