Gerrit Code Review - OpenSource Git Code Review Tool
Refactor.io - Share your code instantly for refactoring and code review
Phabricator - Phacility - Phabricator
codebeat - Automated code review for Swift
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.
Stickler CI - Focus on your project, not formatting.