Terms of service

Last updated: July 26, 2026

1. Acceptance

These terms govern the use of the ZefirCalendar application for Windows and of the website zefircalendar.com.br, provided by Diógenes P. Magnus (Brazil) — "we". By installing or using ZefirCalendar, you agree to these terms. If you do not agree, do not use the application.

2. What ZefirCalendar is

ZefirCalendar is a desktop application for Windows 11 that displays, in the system tray, calendars and events from third-party services you connect, today including iCloud (via CalDAV), Google Calendar (via the official Google API), Outlook and Microsoft 365 (via the official Microsoft API), and calendars published as an iCal/ICS link, and lets you create, edit, and delete events in those services. The application runs locally on your computer and does not depend on any server of ours.

3. License to use

We grant you a personal, non-exclusive, non-transferable, revocable license to install and use ZefirCalendar on Windows devices you own or control, for your own use. You may not redistribute, sell, sublicense, modify, decompile, or reverse-engineer the application, except where the law expressly permits it.

4. Third-party accounts and services

• To connect iCloud, Google Calendar, and Outlook, you use your own credentials with those services, and remain responsible for keeping them secure and for complying with the terms of Apple, Google, and Microsoft.
• ZefirCalendar depends on APIs operated by Apple, Google, and Microsoft. If those services change, limit, or discontinue their APIs, some features may stop working, something outside our control. We will make reasonable efforts to adapt the application when that happens.
• ZefirCalendar is an independent product. It is not affiliated with, endorsed by, or sponsored by Apple, Google, or Microsoft. iCloud, Google Calendar, Outlook, Microsoft 365, Windows, and Microsoft Store are trademarks of their respective owners.

5. Free trial and free tier

ZefirCalendar offers a 7-day free trial with all features, with no payment details required. After the trial, without an active subscription, the application keeps working in a limited mode (such as displaying today's events in the tray), and the full features remain available to subscribers. The exact scope of the free mode may be adjusted over time and is described on the website.

6. Subscriptions, prices, and cancellation

• Full access is offered by subscription (monthly or annual), with prices shown at the time of purchase. Payment is processed by the payment platform (such as the Microsoft Store or the checkout provider indicated at purchase) under its own terms — we never receive your card details.
• Subscriptions renew automatically until cancelled. You can cancel at any time through the platform where you subscribed; access remains active until the end of the paid period, and periods already paid are not refunded pro rata, except where the payment platform's policy or applicable law provides otherwise.
• If you are a consumer in Brazil, your legal right of withdrawal within 7 days of the purchase (art. 49 of the Consumer Protection Code) remains guaranteed.
• Launch or promotional prices honored to active subscribers remain valid while the subscription stays continuously active, as announced on the website. Regular prices may change; changes never apply retroactively to periods already paid.

7. Acceptable use

You agree not to use ZefirCalendar to violate the law, third-party rights, or the terms of Apple, Google, and Microsoft, nor to attempt to circumvent subscription enforcement or interfere with the application's operation.

8. Privacy

The handling of your data is described in the privacy policy, which is part of these terms. In short: your credentials and events stay on your computer, encrypted, and never pass through our servers.

9. Warranties and liability

ZefirCalendar is provided "as is" and "as available". We work to keep it stable and accurate, but we do not guarantee uninterrupted or error-free operation, nor that it will meet every specific need. The application displays and edits data that lives in third-party services; always treat those services as the authoritative source of your calendar.

To the maximum extent permitted by applicable law, our total liability for any claim related to the application is limited to the amount you paid for your subscription in the 12 months preceding the event. Nothing in these terms excludes rights that consumer-protection law grants you and that cannot be waived.

10. Termination

You may stop using ZefirCalendar at any time by uninstalling it. We may suspend or terminate the license in case of relevant breach of these terms. Sections that by their nature should survive (such as liability limits) remain in force.

11. Changes to these terms

We may update these terms; the date at the top will reflect the current version, and relevant changes will be highlighted on the website. Continuing to use the application after a change means you accept the updated terms.

12. Governing law and contact

These terms are governed by the laws of Brazil. If you are a consumer, disputes may be brought before the courts of your own domicile. Questions? Write to suporte@zefircalendar.com.br.