When comparing GitX-dev vs Ungit, the Slant community recommends GitX-dev for most people. In the question“What are the best Git clients for macOS?” GitX-dev is ranked 4th while Ungit is ranked 15th. The most important reason people chose GitX-dev is:
Allows for interactive staging of files or hunks and deleting of unstaged or non-git tracked files. Hunk size slider allows staging/unstaging individual lines, letting you stage pieces of a file easily.
Specs
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Pros
Pro Visual commit mode
Allows for interactive staging of files or hunks and deleting of unstaged or non-git tracked files. Hunk size slider allows staging/unstaging individual lines, letting you stage pieces of a file easily.
Pro Fast GUI
Responsive even with thousands of files or large binary like files
Pro Understandable trees (branches etc.)
The visualisation of the development trees makes git a lot more useful. The command line is good for a lot, but trees are for GUI clients like GitX.

Pro Free and Open Source Software
Ungit is open source software available under the MIT Licence.

Pro Cross-platform
Works on Windows, Linux, and OS X.
Pro Optional Integration with Modern Text Editors
Ungit can be integrated directly into modern text editors, Atom, Brackets, and VS Code.
Pro Web-based interface
Ungit is web-based, meaning you can run it on your cloud/pure shell machine and then use the UI from your browser.
Cons
Con Clumsy staging workflow
The staging workflow in GitX-dev is kind of clumsy and unintuitive in the opinion of some. (others love it)
Con Node.js dependent

Con Setup is not user-friendly
Ungit is distributed as an NPM package and requires git and Node.js to be installed on your system before you can run it. Ungit must be launched by running ungit
in a command line terminal.
Con Exposes git commands to your network
No authentication, if someone can communicate with your computer on the port this is running on, they can execute any git command they want on your repos as well as view your filesystem's folders.
