Review file changes, make commits and manage Git branches from your desktop.
Free and open source (MIT licence per GitHub).

Developer tools
Review commits, manage branches and resolve Git changes with a visual client.
Review commits, manage branches and resolve Git changes with a visual client.
Feature-packed desktop Git client with visual branch trees, interactive hunk staging, and conflict resolution replacing Sublime Merge.
Not open source
Each comparison covers the workflow described above, rather than every paid feature.