Aero Markdown vs MacMD Viewer: which Mac reader fits your files?

What actually separates these two readers?

A README arrives with a specification, an architecture document and a folder of images. You want to read the proposal, follow its references and understand what changes. Both apps are aimed at that broad reading job. The meaningful question is how you want to handle the source while doing it.

MacMD Viewer makes a firm promise: the reading app cannot save changes to your Markdown. Aero Markdown opens on the rendered page too, but provides an explicit editing mode. That is useful when a review reveals a typo or a sentence you need to correct. It also means the two products have different boundaries: one keeps all writing in another app; the other lets you make a correction without leaving the reading window.

If a strict separation between reading and writing matters most, MacMD Viewer has the clearer constraint. If the documentation is already yours to maintain, optional editing may be convenient. Neither approach changes the fact that opening a file in Aero Markdown does not rewrite it.

Features compared

Scroll sideways to compare both apps →

MacMD Viewer’s feature documentation and Quick Look page describe its reading tools. Aero Markdown’s reading features explain the native app’s current scope.

Read a project, rather than one isolated page

Aero Markdown’s window puts the folder tree to the left, the rendered document in the middle and the heading outline to the right. Relative Markdown links open inside the folder, and back and forward remember the place. You can keep the surrounding documents visible while following the argument on the page.

This matters when specification.md sends you to architecture.md and then decisions.md. A heading outline solves movement within one document; a folder tree and link history solve movement between documents. For a single attachment, that extra structure may be unnecessary. For a connected project, it is the workflow worth evaluating.

Do not confuse a screenshot of an outline with evidence about folder navigation. Start with the linked reading kit, follow a requirement to its supporting decision, then return to the requirement. The useful outcome is knowing where you are, without reconstructing the route in Finder.

Reading while a coding agent works

MacMD Viewer documents optional coding-tool integrations. Aero Markdown also has an optional command that the user copies and runs to install local hooks. Auto-opening Markdown is therefore not an exclusive reason to choose either app.

In Aero Markdown, two behaviors are separate. The open document is watched by default, so a rewrite reloads the page at the current heading when you have no unsaved edits. Opening a newly created file requires a supported hook or another explicit open action. Codex is not in the hook list: it can trigger a reload by rewriting the file already open, but creating another file does not make the reader jump to it.

If you have edited the current document too, your text stays intact and the app reports the disk change. See the agent-reading guide for that boundary. This is about reading local output; Aero Markdown has no assistant or model calls.

Price, availability and the sensible choice

MacMD Viewer lists $19.99 once for one active Mac, with transfer terms on its pricing page. Aero Markdown is $14.99 USD, one-time, for a lifetime Aero 1.x license for one Mac. Download and checkout are not available yet.

A price difference is less important than the editing boundary and the documents you read. Choose an available read-only reader when you want source changes to happen elsewhere. Consider Aero Markdown when a folder-oriented reading window and occasional explicit corrections fit your work. If you already have a reader that handles those tasks comfortably, there is no need to replace it just to match a feature list.