Mantis Bug Tracker is a free and open source, web-based bug tracking system. The most common use of MantisBT is to track software defects.

PMRobot is Project Management Software designed exclusively for Software Consulting Companies.

Flyspray is a lightweight, web-based bug tracking system written in PHP for assisting with software development and project managements.

GitPrep is a portable GitHub system.

The Bug Genie is free and open source, web-based project management and bug tracking system.

YouTrack is a commercial browser-based bug tracker, issue tracking system and project management software.

FogBugz is an integrated web-based project management system featuring bug/issue tracking, discussion forums, wikis, customer relationship management, and evi…