Mechanics of Writing

Scrivener for help with research, organization, writing, and formatting an app made exclusively for writers. Also with a user community forum.
Scapple an app like a virtual sheet of paper or a whiteboard. Use it to draw notes of your ideas and connect them using lines, arrows, and more.
Plottr an app to arrange (and rearrange) scenes, plots, and character arcs as you navigate your way to the end of your plot—a virtual corkboard.