Gitscout - A beautiful Github Issues experience for macOS
Zube - Project management for developers.
GitHub Reader - A quick way to browse GitHub issues and pull requests.
ZenHub - ZenHub is how the world's best software teams work together. Trusted by NASA, Docker, and Rackspace. Start free today!
Branches - App for managing issues for your GitHub, GitLab or Bitbucket
Huboard - HuBoard is built from the ground up using the GitHub public API.