I am using Obsidian on my Mac. I am using Google Drive to sync the notes (md, images, and audio).
I am an iPhone user and I downloaded Google Drive app to view my notes (md, images, audio). Google drive don’t let me view md file and gives unsupported error.
I tried few free markdown ios apps ( Pretext, Blockquote etc.) which failed to open markdown file from File app where Google Drive is available as an option.
I used Safari browser and accessed drive.google.com. I was able to view markdown in preview.
I was able to open the markdown file for editing in Safari browser using Google Drive open with stackeditor option. Stackeditor add some config code in each file which is bothering.
I also found an app called Quick Editor - Text & Code which integrates with Google Drive and let me view and edit single markdown file effectively on iphone.
Remember its not full blown markdown editor which show inline image or link etc. It is an ad supported app. I am satisfied with it as of now. However I like to have a better md app with Google Drive integration.