# Privacy Policy

How MarsDawn, the Markdown app for Mac, iPhone and iPad, handles your information.

Last updated 2026-10-29

> **The MarsDawn app does not collect any data about you.** There is no account, no advertising and no tracking. Your documents and settings stay on your devices.

## The website

The app and this website are two different things. The app collects nothing. A visit can be recorded only here, on marsdawn.southern-light.dev.

This site uses **Google Analytics 4**, loaded through **Google Tag Manager**. Every visitor starts with analytics denied: Google's Consent Mode sends only a cookieless ping with no analytics cookie and no persistent identifier, until you choose *Accept* in the banner. Choosing *Decline*, or making no choice at all, keeps it that way, and choosing *Decline* after a prior *Accept* turns analytics back off immediately and removes the cookies below. Change your choice at any time with the "Cookie settings" link in the footer of every page. The choice itself is stored only in your browser's local storage, never in a cookie of ours.

Once you accept, Google Analytics sets its own cookies (`_ga` and `_ga_<measurement id>`) and records:

- **Page views and referrer.** Which page was viewed, and the referring address when the browser sends one.
- **Approximate location, device and browser.** A coarse location derived from your IP address (city level at most), your device type, operating system and browser — none of it precise enough to identify you.
- **Outbound clicks and scroll depth.** Google Analytics' enhanced measurement records clicks that leave the site, such as the link to the Mac App Store, and how far you scroll down a page.
- **IP addresses.** Google Analytics 4 does not log or store IP addresses.
- **What is not recorded.** No account, because the site has none. No document, and nothing you type. No cross-site advertising, and no profile of you. Requests the app makes for theme files under `/themes/` are skipped, and are not sent on. The theme simulator and gallery on `/themes/new/` and `/themes/gallery/` run entirely in your browser and send no theme data to Google Analytics either.
- **Retention.** Google keeps this data for 14 months, then deletes it.
- **Where it's processed.** Google Tag Manager and Google Analytics are operated by Google; your data may be processed in the United States as well as other countries where Google operates.
- **The host.** Cloudflare hosts the site and, like any host, sees your IP address while it answers the request. That log belongs to the host. It is not the analytics above.

## Launch survey

From 26 October to 8 November 2026, MarsDawn runs a short survey on Google Forms. Filling it in is up to you, and the app itself still collects nothing.

- **What it collects.** Your answers and the email address you type. Nothing else.
- **The email.** It's used to send a code to the first 500 respondents. If you don't tick the update box, it's deleted within 30 days after the codes are sent. If you tick it, it's kept only to send MarsDawn version-update emails, each with a one-click unsubscribe, until you unsubscribe.
- **The answers.** After the survey closes they're kept without the email, and they may appear anonymised and aggregated in a published summary.
- **Never shared or sold,** and never used for anything else.
- **Where it's stored.** Google Forms stores the responses with Google, under Google's privacy policy.
- **Deletion.** To have your response or email deleted sooner, write to support@southern-light.dev.

## What stays on your Mac

- **Your documents.** MarsDawn reads and writes only the files and folders you open, save or choose. They are never uploaded anywhere by the app.
- **Your settings.** Appearance, preview theme, window layout and the image preference are stored in the app's own preferences on your Mac.
- **Folder access you grant.** When you let MarsDawn show images or page files from a folder, or choose a notes folder, the app keeps a macOS bookmark so it can open that folder again. A folder you open in the sidebar stays readable and writable by MarsDawn until you remove it in Settings, not just while its window is open. You can remove folders at any time in MarsDawn › Settings.

## When MarsDawn uses the internet

MarsDawn works fully offline. It connects to the internet only **when you choose to**: for a document that refers to the web, or for the theme gallery. For documents:

- **Markdown documents.** Web images are blocked by default. They load only after you click *Load Images* in the preview, or if you turn on *Load remote images automatically* in Settings. Nothing else a Markdown document refers to is loaded from the web.
- **HTML documents.** An HTML document opens static: its code doesn't run and nothing is loaded from the web. If a document contains code that could run, you can choose *View › Run This Document* for that document. Its own code then runs until you stop it, the document reloads or you close the window. That choice is never remembered, and it isn't a setting. While it runs, the document can send data over the network, and read images, style sheets, fonts and media in its folder and the folders inside it. Code downloaded from the web never runs.

MarsDawn loads web content over https only. A plain http address is never loaded, in any setting, and MarsDawn does not rewrite it to https. In a Markdown document, the preview shows a placeholder in its place.

When web content loads, your Mac requests it directly from the servers that host it. Like any web request, this lets those servers see your IP address and what was requested. MarsDawn's developer receives none of this information.

Links you click in the preview open in your default web browser, under that browser's own privacy practices. Audio and video never play by themselves.

If you open *Settings › Appearance › Get More Themes…*, choose *Check for Theme Updates*, or install or update a theme, MarsDawn downloads the theme list, previews and theme files from marsdawn.southern-light.dev. Themes update automatically only during these downloads, never in the background. The request carries no account, identifier, cookie or document data; like any web request, our host Cloudflare sees your IP address and which files were requested. *Report Theme…* makes no request from the app: it only opens a GitHub or email link in your browser or mail app.

## Siri, Shortcuts and Spotlight

MarsDawn offers actions for Siri, the Shortcuts app and Spotlight, such as creating a document or adding a note. When you use them, the text you provide is passed to MarsDawn on your Mac and saved only where the action says (a new document, or the `Inbox.md` file in the notes folder you chose). Speech you dictate to Siri is handled by Apple under [Apple's Privacy Policy](https://www.apple.com/legal/privacy/).

## Exporting and printing

PDF export and printing happen on your Mac. The PDF is saved where you choose. Printing goes through macOS to the printer you pick.

## The marsdawn command-line tool

The optional `marsdawn` command-line tool, distributed separately, also runs entirely on your Mac. It reads the Markdown file you name and writes the PDF you ask for. It loads web images only when you pass `--allow-remote-images`.

## Children

The MarsDawn app does not collect data from anyone, including children. A visit recorded on the website is not an account, and it is not used to identify anyone.

## Purchases

MarsDawn is sold through the App Store, for Mac, iPhone and iPad. Apple processes the purchase under its own terms, and the developer never receives your payment details.

## Changes to this policy

If MarsDawn ever starts handling data differently, this page will be updated before that version is released, and the date at the top will change.

## Contact

Questions about privacy: [support@southern-light.dev](mailto:support@southern-light.dev)

## More

- [MarsDawn](https://marsdawn.southern-light.dev/index.md): Read and review the Markdown your agent wrote, natively on Mac: live split preview, Mermaid, KaTeX, Quick Look, PDF export. Free to try, USD 4.99 once.
- [Features](https://marsdawn.southern-light.dev/features/index.md): A native Mac Markdown editor: live preview, Mermaid and math, themes, plus clean PDF and print pages for meetings, margin notes and paper records.
- [Your writing stays on your Mac](https://marsdawn.southern-light.dev/yours/index.md): MarsDawn has no account, no sync and no cloud. Your Markdown documents stay on your Mac, in the files and folders you choose.
- [Try free, pay once](https://marsdawn.southern-light.dev/pay-once/index.md): MarsDawn is free to download. Try everything for 14 days, then unlock it once for USD 4.99. No subscription, no account.
- [PDF export](https://marsdawn.southern-light.dev/pdf/index.md): Export Markdown as a PDF or print it on your Mac, with Mermaid diagrams and highlighted code. Page breaks avoid splitting short code blocks.
- [A Mac app](https://marsdawn.southern-light.dev/native/index.md): A Markdown editor that is a real Mac app: native windows and tabs, autosave, version history, Quick Look in Finder and a text editor that behaves like a Mac.
- [What MarsDawn doesn't do](https://marsdawn.southern-light.dev/limits/index.md): No sync, no editing on iPhone or iPad, no plugins, no accounts. Themes, but no custom CSS. Know before you buy.
- [Support](https://marsdawn.southern-light.dev/support/index.md): Get help with MarsDawn, the Markdown editor for macOS.
- [How to open .md files on Mac](https://marsdawn.southern-light.dev/view-markdown-on-mac/index.md): How to open a .md file on a Mac: double-click, set a default app, preview in Finder. For .md files an AI agent wrote, read them rendered in MarsDawn.
- [Mermaid preview on Mac](https://marsdawn.southern-light.dev/mermaid-preview-mac/index.md): See Mermaid diagrams drawn next to your Markdown on a Mac: live preview, Quick Look and PDF export. A broken diagram shows its error and the line.
- [Quick Look for Markdown](https://marsdawn.southern-light.dev/quicklook/index.md): MarsDawn's Quick Look renders Markdown in Finder when you press Space, with Mermaid, KaTeX and highlighted code. It keeps working after the trial ends.
- [Markdown to PDF](https://marsdawn.southern-light.dev/markdown-to-pdf/index.md): Convert Markdown to PDF on a Mac with the free marsdawn command-line tool. Install it with Homebrew and run one command: tables, math, Mermaid and code.
- [MarsDawn compared: VS Code preview, Obsidian, QLMarkdown, LynxOffice](https://marsdawn.southern-light.dev/vs/index.md): For anyone choosing how to read and review Markdown on a Mac, often what an agent wrote. Every cell below comes from the vendor's own pages or our own check, all on 16 October 2026; products change, so a cell can go stale. If you spot a mistake, write to the address on Support.
- [MacMD Viewer vs. MarsDawn](https://marsdawn.southern-light.dev/vs/macmd-viewer/index.md): MacMD Viewer is a read-only Markdown viewer for USD 19.99. MarsDawn edits and previews side by side: free for 14 days, then USD 4.99 once.
- [Best Markdown viewer for Mac (2026)](https://marsdawn.southern-light.dev/best-markdown-viewer-mac/index.md): Eight Markdown viewers for Mac compared by price, Mermaid, math, PDF, live reload, Quick Look and native vs Electron, with who each one suits.
- [Command Line](https://marsdawn.southern-light.dev/cli/index.md): The free marsdawn command-line tool for Mac: export Markdown to PDF from a shell, a script or an LLM agent, with JSON output. Install it with Homebrew.
- [marsdawn for agents](https://marsdawn.southern-light.dev/cli/agents/index.md): A reference for AI agents and scripts that call marsdawn to turn Markdown into PDF: commands, JSON output, schemas, exit codes and requirements.
- [Agent skill](https://marsdawn.southern-light.dev/cli/skill/index.md): One file your coding agent loads to open Markdown it wrote in MarsDawn for your review, and to install marsdawn, export Markdown to PDF and read the JSON result.
- [MCP server](https://marsdawn.southern-light.dev/cli/mcp/index.md): marsdawn has no AI model of its own, so it doesn't matter which agent wrote the Markdown. Call it from the CLI, a skill file, or the marsdawn-mcp MCP server: all three run the same export.
- [Token-efficient review](https://marsdawn.southern-light.dev/token-efficient-review/index.md): A person reviews the rendered page in MarsDawn, never read back into the agent's context. The tool call itself returns a compact JSON result, not the rendered content, so calling it is cheap too.
- [Viewing Markdown elsewhere vs. MarsDawn](https://marsdawn.southern-light.dev/vs/markdown-preview-tools/index.md): How MarsDawn compares to reading Markdown in VS Code's built-in preview, a browser extension, or Claude Desktop's file preview: what each renders, and what it takes to open one file.
- [Themes](https://marsdawn.southern-light.dev/themes/index.md): Four built-in preview themes, each light and dark, plus a curated gallery you open from Settings in MarsDawn for Mac. Quick Look uses your theme.
- [Build a theme](https://marsdawn.southern-light.dev/themes/new/index.md): Pick colours and a handful of style options, see them applied to a sample document live, and submit your theme as a GitHub issue. No install, no git.
- [Make a theme with your agent](https://marsdawn.southern-light.dev/themes/agents/index.md): MarsDawn theme reference for AI agents: each theme.json field with type and range, the CLI loop that checks and renders it, a hand-off link, and how to submit.
- [Theme gallery](https://marsdawn.southern-light.dev/themes/gallery/index.md): Browse preview themes for MarsDawn, each reviewed by the developer, filter them by scenario, and report a problem with one. Build your own in the browser.
- [Sharing exported PDFs](https://marsdawn.southern-light.dev/sharing-exported-pdfs/index.md): Export an agent's Markdown to PDF and hand it to a colleague who doesn't read Markdown and won't install anything. No syntax, no app and no account needed to open it.
- [Why AI output still needs a human reader](https://marsdawn.southern-light.dev/reviewing-ai-output/index.md): AI-written Markdown still has to be understood by a person, not trusted on sight. MarsDawn pairs the rendered page with the source, and draws Mermaid diagrams and KaTeX math, so structure is legible at a glance.
- [Reading what your agent hands back](https://marsdawn.southern-light.dev/reading-agent-output/index.md): AI agents hand back their work as Markdown: plans, specs, progress reports. What people who build agents say about checkpoints and failures, why that output is hard to read, and a five-minute checklist for reviewing a plan.
- [Agent transparency](https://marsdawn.southern-light.dev/agent-transparency/index.md): Anthropic's guide to building agents asks for transparency: show the planning steps. What it says, what it doesn't, and why the steps usually end up as a Markdown file someone has to read.
- [Reviewing an agent plan](https://marsdawn.southern-light.dev/reviewing-agent-plans/index.md): A six-step way to review the plan an AI agent hands you before it runs, in about five minutes and in any editor, with a worked example.
- [Agent design patterns](https://marsdawn.southern-light.dev/agent-design-patterns/index.md): Reflection, tool use, planning and multi-agent collaboration, as Andrew Ng described them, and what each tends to hand back for you to read.
- [Changelog](https://marsdawn.southern-light.dev/changelog/index.md): What changed in each version of the MarsDawn app and the free marsdawn CLI.
- [Roadmap](https://marsdawn.southern-light.dev/roadmap/index.md): What's in progress and what's next for MarsDawn on Mac, iPhone and iPad, by version. No dates, and unscheduled ideas are marked.
- [Editor's reading notes](https://marsdawn.southern-light.dev/reading-notes/index.md): Six short notes on what the people building AI agents actually argue — Anthropic, Chip Huyen, Lilian Weng, Harrison Chase, LangChain and Andrew Ng — and what each one means for the person who has to read what such an agent hands back.
- [Reading notes: Anthropic](https://marsdawn.southern-light.dev/reading-notes/anthropic-building-effective-agents/index.md): Anthropic's December 2024 guide for people building agents separates workflows from agents and describes five workflow patterns, including one where a second LLM call reviews the first. What that means for what lands in your folder.
- [Reading notes: Chip Huyen](https://marsdawn.southern-light.dev/reading-notes/chip-huyen-agents/index.md): Chip Huyen's January 2025 essay on agents splits their actions into read-only and write actions. Why that split is a fast way to spot the line in a plan worth a closer look before you approve it.
- [Reading notes: Lilian Weng](https://marsdawn.southern-light.dev/reading-notes/lilian-weng-llm-agents/index.md): Lilian Weng's widely cited 2023 survey describes an LLM agent as a brain plus planning, memory and tool use. What each part tends to leave behind for you to read, and the limitation she names in plans that don't adjust to surprises.
- [Reading notes: Harrison Chase](https://marsdawn.southern-light.dev/reading-notes/harrison-chase-what-is-an-agent/index.md): Harrison Chase's 2024 definition of an agent and his spectrum of agentic behavior, and his case for observability as a system moves along it — read from the side of whoever reads the file it hands back.
- [Reading notes: LangChain (Jess Ou)](https://marsdawn.southern-light.dev/reading-notes/langchain-what-is-an-agent/index.md): LangChain's 2026 “What is an AI agent?” by Jess Ou echoes Harrison Chase's 2024 definition and describes a pipeline for evaluating agents automatically. Where that pipeline still hands a step to a person, and where it doesn't.
- [Reading notes: Andrew Ng](https://marsdawn.southern-light.dev/reading-notes/andrew-ng-design-patterns/index.md): Across five letters in The Batch, Andrew Ng ranks reflection, tool use, planning and multi-agent collaboration by how reliable and predictable he finds each one — and what that ranking suggests about how closely to check each one's output.
- [Templates](https://marsdawn.southern-light.dev/templates/index.md): Markdown templates for the documents an agent writes and you read: a spec, a flowchart and meeting notes, each with a prompt for your agent.
- [Spec template](https://marsdawn.southern-light.dev/templates/spec/index.md): A Markdown spec template with requirements, a Mermaid flow diagram and acceptance criteria. Your agent fills it in; you review it in MarsDawn.
- [Flowchart template](https://marsdawn.southern-light.dev/templates/flowchart/index.md): A Mermaid flowchart template in Markdown, with the steps written out below it. Preview it on a Mac and export it to PDF.
- [Meeting notes template](https://marsdawn.southern-light.dev/templates/meeting-notes/index.md): A Markdown meeting notes template with decisions and action items, each with an owner. Your agent writes it up; you check it in MarsDawn.
- [繁體中文](https://marsdawn.southern-light.dev/zh-hant/privacy/index.md): MarsDawn 不收集任何個人資料，你的文件與設定都留在你的 Mac 上。
- [简体中文](https://marsdawn.southern-light.dev/zh-hans/privacy/index.md): MarsDawn 不收集任何个人数据，你的文稿与设置都留在你的 Mac 上。
- [日本語](https://marsdawn.southern-light.dev/ja/privacy/index.md): MarsDawn は個人データを収集しません。文書と設定はあなたの Mac 上に残ります。
- [Deutsch](https://marsdawn.southern-light.dev/de/privacy/index.md): MarsDawn erhebt keine personenbezogenen Daten. Deine Dokumente und Einstellungen bleiben auf deinem Mac.
- [Français](https://marsdawn.southern-light.dev/fr/privacy/index.md): MarsDawn ne collecte aucune donnée personnelle. Vos documents et vos réglages restent sur votre Mac.
- [Español](https://marsdawn.southern-light.dev/es/privacy/index.md): MarsDawn no recopila datos personales. Tus documentos y tus ajustes se quedan en tu Mac.
- [한국어](https://marsdawn.southern-light.dev/ko/privacy/index.md): MarsDawn은 개인정보를 수집하지 않습니다. 문서와 설정은 사용자의 Mac에 남습니다.