Do you mean how your notes are connected, and organized? Otherwise, they are plain-text Markdown files. Any app that renders Markdown should be able to do it.
In-fact, I don’t really like Obsidian on Mobile, so I use iA-Writer to edit/view the Markdown files that I managed with Obsidian on the Desktop.
In-fact, I don’t really like Obsidian on Mobile, so I use iA-Writer to edit/view the Markdown files that I managed with Obsidian on the Desktop.