Last updated September 26, 2026
This policy explains how Zeller Holdings Inc., the company that makes Muster ("Muster", "we", "us"), handles information when you use the Muster Android app and the website at usemuster.app (together, the "Service").
Muster is used by construction companies and their teams. The company that signs up (our "customer") decides who joins and what goes into its account. For the work records your company puts into Muster, we act on the company's behalf. If you have questions about how your employer uses Muster, ask them too.
What we collect
Account information
Your name, email address, optional phone number, password (stored only as a secure hash), your role in the company and, if added, your trade. For the company: its name and the details of its projects, such as project names, numbers, clients, addresses and site locations.
Work records
What you and your team enter to run the job: time entries and breaks, timesheet approvals, daily logs, tasks and punch list items, comments, safety incident reports (which can include details about an injured person), toolbox talk attendance and sign-offs, and material requests.
Location
With your permission, the app reads your device's location only at the moment you clock in or clock out. We compare it with the project's site boundary (geofence) and record whether you were on site. We do not track your location in the background or between clock events. If location isn't available, the entry is recorded without an on-site check.
Photos you add to a project can include the place they were taken, if your device provides it.
Photos and documents
Photos and files you upload, such as progress photos, punch list photos, incident photos, drawings, specs, permits and contracts.
Subscription information
Subscriptions are sold and billed by Google Play. We receive the purchase details we need to confirm your plan, such as the product, purchase token, status and renewal date. We never see or store your card or bank details.
Technical information
Basic information needed to run and secure the Service, such as IP address, device type, operating system and app version, and server logs of requests and errors.
When you contact us
If you email us, we keep the conversation so we can help you.
How we use it
- To provide the Service: sign you in, show your company's projects and records, and let your team work together.
- To flag clock events made away from the project site, so your company can review them.
- To send service emails, such as password reset codes, invites your company sends, and incident notifications to owners and managers.
- To confirm your subscription and seat limit with Google Play.
- To keep the Service secure, prevent abuse and fix problems.
- To answer support requests.
We don't sell your information, and we don't use it for advertising.
Who can see it
- People in your company, based on their role. For example, owners and managers can see all projects and time entries, foremen see the projects they run, and crew members see their own time entries and the projects they're on.
- Service providers who help us run Muster, such as cloud hosting, file storage and email delivery. They may only use the information to provide their service to us.
- Google, for subscription billing through Google Play, under Google's own privacy policy.
- Authorities, if the law requires it, or to protect the safety of people or the Service.
- A buyer or successor, if Muster is involved in a merger or sale, under this policy's protections.
How long we keep it
We keep your information for as long as your account and your company's account are active. When you delete your account, we delete your personal information. When a company owner deletes their account, we delete the whole company: its projects, records, photos and documents. Deleted data is removed from backups on their normal rotation.
We may keep a small amount of information longer where the law requires it, such as billing records, or to resolve disputes and prevent abuse. See Delete your account for details.
How we protect it
Data is encrypted in transit. Files are stored privately and shared only through short-lived links. Passwords are stored as secure hashes. Access inside your company follows the roles your company sets. No system is perfectly secure, but we work to protect your information and will tell affected customers about a breach as the law requires.
Your choices and rights
- See and correct your profile in the app at any time.
- Location: turn location permission on or off in your device settings.
- Delete your account in the app under More → Delete account, or see other options.
- Access, copy or delete other information: email us. Depending on where you live, you may have further rights, such as to object to or restrict certain processing, or to complain to your local data protection authority.
If your request is about records your company controls, such as time entries, we may need to work with your company to respond.
Children
Muster is a work tool for businesses. It isn't meant for anyone under 16, and we don't knowingly collect information from children.
International transfers
We and our service providers may store and process information in countries other than yours, including the United States. Where required, we use appropriate safeguards for these transfers.
Changes to this policy
If we make important changes, we'll update the date at the top and let account owners know by email or in the app before they take effect.
Contact us
Questions or requests: [email protected].