Computer Aided Textual Markup & Analysis (CATMA) (GPL v3 license). CATMA 4 is implemented as a web-based application.
Pros and cons
Such software helps to organize, manage and analyse information.  The advantages of using this software include being freed from manual and clerical tasks, saving precious time, managing huge amounts of qualitative data, having increased flexibility, and having improved validity and auditability of qualitative research. Concerns include increasingly deterministic and rigid processes, privileging of coding, and retrieval methods; reification of data, increased pressure on researchers to focus on volume and breadth rather than on depth and meaning, time and energy spent learning to use computer packages, increased commercialism, and distraction from the real work of analysis.
^Banner, DJ; Albarrran, JW (2009). "Computer-assisted qualitative data analysis software: a review.". Canadian journal of cardiovascular nursing = Journal canadien en soins infirmiers cardio-vasculaires19 (3): 24–31. PMID19694114.Cite uses deprecated parameters (help);|accessdate= requires |url= (help)
^St John, W; Johnson, P (2000). "The pros and cons of data analysis software for qualitative research.". Journal of nursing scholarship : an official publication of Sigma Theta Tau International Honor Society of Nursing / Sigma Theta Tau32 (4): 393–7. PMID11140204.Cite uses deprecated parameters (help);|accessdate= requires |url= (help)