Ranked in these QuestionsQuestion Ranking
Pro Real-time HTML Preview
MarkdownPad is split in two panes. One pane is used for writing Markdown, the other shows the rendered HTML as it's written.
Pro Allows customizing output
A custom CSS can be added to the rendered HTML to change the preview and output.
Con Abandoned project
Con Many features are disabled in the free version
Free version lacks features like auto-save, PDF export, Markdown tables among many others and can't be used commercially.