OSOR - OSOR is the Open Source Observatory, a project to provide a framework for developing and executing autonomous observations.
Shrink for Github - A macOS app for your Github issues
SourceForge - The Complete Open-Source and Business Software Platform.
GitHub Reader - A quick way to browse GitHub issues and pull requests.
openDesktop.org - The website openDesktop.
Codetree - You can manage your entire development process through GitHub.