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.
Taskade - Make lists, organize your thoughts, and be inspired to get things done. Taskade is a collaborative space for your tasks.
Planyway - Visual project management for Jira and Trello: manage resources, build project roadmaps, use time tracking.
Kropply - Reduce your debugging time with the power of AI
Corrello - Dashboards for agile teams using Trello
Snypt - A coding collaboration platform for snippets of code.