There's no shortage of writing apps for OS X, for any type of work, and for any budget. You may want to stick with the free TextEdit, or, if you use Markdown, look for a tool that displays formatted texts better. My ideal text editor would have the simplicity of iA Writer, some of the features of ByWord and WriteRoom, and the preview and export features of Marked 2. Sadly, such a dream app doesn't exist. In its absence, I've found iA Writer to be the most useful tool, because it stays out of my way.
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