SlimPlanner - Team scheduling, resource planning, task management
Mergify - Stop merging your pull requests manually
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.
Mergefly - A modern UI for GitHub pull requests
WorkPatterns - The modern manager's toolkit: 1:1s, feedback, & recognition
PR Patrol - Monitor code that matters to you