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.
CTO.ai - Build, share & run developer workflows in the CLI + Slack
Planyway - Visual project management for Jira and Trello: manage resources, build project roadmaps, use time tracking.
Webiny - The Enterprise CMS platform that you can host on your cloud
Corrello - Dashboards for agile teams using Trello
Kosmo - Kosmo helps you automate your freelancing business. Including sending invoices, tracking time, managing projects and more.