Simple Markdown is a free and open-source markdown editor for Android devices. It provides a straightforward and efficient way to edit markdown files, making it a great tool for developers, bloggers, and writers.

The app has a clean and intuitive user interface, making it easy to use for beginners. It supports the basic markdown syntax, including headings, bold, italic, and links. Additionally, it provides a preview mode that allows users to see how their markdown document will look like when rendered.

Overall, Simple Markdown is a great app for anyone who needs to edit markdown files on-the-go. However, it lacks some advanced features that power users may require, such as support for tables and code highlighting. Also, the app's developer is open to feedback and bug reports, which is always a plus.