Contributions for GitHub - Show your GitHub contributions graph on your iOS Devices
Refined GitHub - Browser extension that makes GitHub cleaner & more powerful
GitHub Visualizer - Enter user/repo and see the project visually
GitZip - Download or create a download link for a GitHub project folder/sub-folder or file.
GitHub Gardener - Daily, automated commits that turn your GitHub green
DownGit - Directly download or create download links to GitHub public folders or files.