As I’ve posted before, Scrivener is my writing environment of choice. I use if for my current book project and for client reports in my consulting business.
It’s chief competitor is Ulysses, which I have not used. Writer Chris Rosser uses both and provides this comparative analysis of the two. While portions are a bit über-techie, Rosser provides one of the most succinct descriptions of what sets Scrivener apart from a mere word processing program.