Privacy policy

Last updated 2026-10-23

The short version

Muster does not collect, send or sell any information about you. The app and this website have no analytics, no trackers and no accounts.

The Muster app

• The app does not send usage data, crash reports or anything else to us or to anyone else.
• It works without an internet connection. The one request it can make is the update check: when you press Check for updates, or each time it starts if you turn that on (it is off by default), Muster asks GitHub for a short file naming the latest version. The request carries nothing about you; GitHub sees your IP address, as with any request. If you choose to install an update, Muster downloads it from GitHub and checks its signature first.
• The window is drawn by your system's own web view: WebKit on macOS, WebView2 on Windows, WebKitGTK on Linux. On Windows, Muster turns off Microsoft SmartScreen in it, so the pages it shows are not sent to Microsoft for checking. Your system keeps the web view up to date, not Muster.
• Your apps, groups, themes, settings and the programs you approved to run are saved in a file on your own computer. They are never uploaded.
• To find installed apps, Muster reads app names, icons and launch commands from the standard app folders. It does not read your documents, recent files or browser data.
• When you close a group, Muster looks at the programs running under your account to find the group's apps, asks them to quit, and offers to force quit any that stay open. It keeps nothing from that list once it is done.
• If you turn on start on login, Muster adds one entry to your system's list of programs to start when you log in. It holds only where Muster is installed. Turning the setting off removes it.
• Muster stores no passwords, tokens or keys.

This website

• The website sets no cookies and runs no scripts.
• It loads nothing from other companies: no fonts, images, scripts or embeds.
• The server that hosts it may keep standard access logs (IP address, time, page requested, browser name) to keep it running and secure. These logs are not used to track you and are not shared.
• The site is delivered through Cloudflare, which sees each request, including your IP address, under Cloudflare's privacy policy. Cloudflare also asks browsers to report network errors: if loading a page fails, some browsers send Cloudflare a short note saying which page and what went wrong. This does not change the page.
• The download button sends you to GitHub, where GitHub's privacy statement applies.

Changes

If this ever changes, the change will be described in the release notes and on this page before it ships. The source code is public on GitHub, so anyone can check.

Contact

Questions: muster@vainnor.com