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.
Kitemaker - A fast issue tracker for makers and innovators
Notion - All-in-one workspace. One tool for your whole team. Write, plan, and get organized.
Linear - Streamlined issue tracking for software teams
Slack - A messaging app for teams who see through the Earth!
Triage & Timeline by Linear - The issue tracking tool you'll enjoy using