GitKraken - The intuitive, fast, and beautiful cross-platform Git client.
PuTTY - Popular free terminal application. Mostly used as an SSH client.
SourceTree - Mac and Windows client for Mercurial and Git.
MobaXterm - Enhanced terminal for Windows with X11 server, tabbed SSH client, network tools and much more
GitHub Desktop - GitHub Desktop is a seamless way to contribute to projects on GitHub and GitHub Enterprise.
iTerm2 - A terminal emulator for macOS that does amazing things.