Codacy - Automatically reviews code style, security, duplication, complexity, and coverage on every change while tracking code quality throughout your sprints.
Understand - Combines a powerful Code Editor together with an impressive array of static analysis tools that will change the way you work with code.
CodeClimate - Code Climate provides automated code review for your apps, letting you fix quality and security issues before they hit production. We check every commit, branch and pull request for changes in quality and potential vulnerabilities.
Sourcetrail - Sourcetrail is a cross-platform source explorer for C/C++ and Java.
SonarQube - SonarQube, a core component of the Sonar solution, is an open source, self-managed tool that systematically helps developers and organizations deliver Clean Code.
CodeCompass - CodeCompass is an extensible code comprehension tool.