OmniFocus is a personal task manager by The Omni Group for macOS and iOS. The declared goal of the program is to be able to capture thoughts and ideas into to do lists. The program uses concepts and techniques described in the book Getting Things Done by David Allen.
GitHub is a web-based hosting service for version control using git. It is mostly used for computer code. It offers all of the distributed version control and source code management functionality of Git as well as adding its own features