Muster
Muster app Privacy Policy
Last updated 26 September 2026
Muster organises groups and their events: who is in a group, which events are on, and who is playing. This policy explains what Muster stores, who can see it, and how to remove it.
What Muster stores
- Your email address, to sign you in with a one-time code and to send you group and event invitations.
- Your name, as you enter it, so other members know who you are.
- Your activity in groups: the groups you belong to and your role in them, the events you are invited to, your replies (in or out), and your place in any standby queue.
- Things you create: group names, events (title, time, place, capacity), and invitations you send, including the email addresses you invite.
Muster has no ads, no analytics and no tracking, and does not sell or rent your data.
Who can see it
- Members of a group see each other's names, and for events in that group, everyone's replies and the standby queue.
- Group admins also see the email addresses of people invited to the group who have not joined yet.
- When you are invited to a group, you see the name of the person who invited you.
- Your email address is not shown to other members.
Services that process it
Muster runs on these providers, which handle data only to provide their service:
- Supabase hosts the database and the sign-in system.
- Resend sends sign-in codes and invitation emails. It receives the recipient's address and the email's contents, and keeps delivery logs for a limited time.
- Cloudflare hosts the web app. Like any web host, it sees your IP address when you load the site.
All connections are encrypted in transit. The app keeps your sign-in session on your device so you stay signed in.
How long it is kept
Your data is kept while you have an account. You can change your name at any time in Settings.
Deleting your account
You can delete your account yourself, in the app under Settings, or by following these steps. Deletion is immediate and removes your name, email address, memberships, replies, standby places and invitations sent to your address. Groups and events you created stay for their other members, no longer linked to you. Groups where you are the only admin are archived.
Children
Muster is not directed at children under 13, and we do not knowingly collect their data.
Changes
If this policy changes, the new version will be posted here with a new date.
Contact
Questions about your data: support@musterapp.fyi