Check out Epsilon Notes
https://play.google.com/store/apps/d...artoyev.enotes
It's an editor, but can also preview Markdown files and it has a file manager inside. It's what I use for writing Markdown on Android and I like it a lot. You can grab it from the Play Store and then later move the apk to another device, it doesn't need Google Play Services to work (you will lose Premium features if you bought them, though).