Been working on a space opera for about a year, and the biggest lesson is that the right tool changes with each draft phase. For the initial vomit draft, you just need something frictionless. I used an old word processor called FocusWriter for a while because it blocked out everything else. The temptation to fiddle with formatting is real. At that stage, any software with a 'fullscreen' mode works. Once you have a manuscript, that's when you need structure. I moved everything into Scrivener. It's not intuitive, but the ability to drag scenes around like notecards and store research in the same file is a lifesaver. I think a lot of people buy it expecting magic and get overwhelmed; you have to be ready to learn it. For the final polish, Word or Google Docs is fine because that's what editors and beta readers use. No one wants to download some weird file.
Another thing, distraction-free tools are a dime a dozen. Write or Die was kind of brutal, but it got me through my last NaNoWriMo. The key isn't finding the perfect app, it's committing to the one you have and understanding what job you need it to do at each stage of the process. My writing group has one person who still writes everything longhand, which seems insane to me, but they have three published books, so what do I know.