GitHub - Originally founded as a project to simplify sharing code, GitHub has grown into an application used by over a million people to store over two million code repositories, making GitHub the largest code host in the world.
SmartGit - SmartGit is a front-end for the distributed version control system Git and runs on Windows, Mac OS...
Gerrit Code Review - OpenSource Git Code Review Tool
SourceTree - Mac and Windows client for Mercurial and Git.
Phabricator - Phacility - Phabricator
GitKraken - The intuitive, fast, and beautiful cross-platform Git client.