Code Review Tools
gocover.io
Code coverage for any Go package
reviewable.io
Code review for GitHub repositories, free for public or personal repos
codecov.io
Code coverage tool (SaaS), free for Open Source and one free private repo
webceo.com
SEO tools but with also code verifications and different types of devices
browserling.com
Live interactive cross-browser testing, free only 3 minutes sessions with MS IE 9 under Vista at 1024 x 768 resolution
deepscan.io
Advanced static analysis for automatically finding runtime errors in JavaScript code, free for Open Source
scrutinizer-ci.com
Continuous inspection platform, free for Open Source
semanticdiff.com
Programming language aware diff for GitHub pull requests and commits, free for public repositories
scan.coverity.com
Static code analysis for Java, C/C++, C# and JavaScript, free for Open Source
goreportcard.com
Code Quality for Go projects, free for Open Source
gerrithub.io
Gerrit code review for GitHub repositories for free
houndci.com
Comments on GitHub commits about code quality, free for Open Source