GitPigeon - GitHub notifications delivered to your Mac
GitHub Polls - Polls for GitHub issues and readme
Gitify - GitHub Notifications on your desktop.
Octotree - Github on steroids
Neat.run - Neat puts SaaS notifications in your menu bar. Streamline your code review and ship with ease. Preview, triage, and jump to issues in one click or keystroke.
Octobox - Untangle your GitHub Notifications