Zero Calendar

Privacy Policy

Last updated: May 28, 2025

1. Introduction

Welcome to Zero Calendar ("Service", "we", "us", or "our"). We are committed to protecting your personal information and your right to privacy. If you have any questions or concerns about this privacy policy, or our practices with regards to your personal information, please contact us (see Section 10 "Contact Us").

This privacy policy describes how we might use your information if you:

  • Visit our website and use our services.
  • Engage with us in other related ways, including any sales, marketing, or events.

In this privacy policy, if we refer to:

  • "Service", we are referring to our website and calendar application.
  • "Personal Information", we mean any information that identifies you as an individual.

2. Information We Collect

We collect Personal Information that you voluntarily provide to us when you register on the Service, express an interest in obtaining information about us or our products and services, when you participate in activities on the Service, or otherwise when you contact us.

2.1. Information You Provide to Us

  • Account Information: When you create an account via Google Sign-In, we collect your name and email address as provided by Google. We also store your preferred timezone, which may be automatically detected or manually set by you. This information is necessary for creating and managing your account.
  • Calendar Data: When you use our Service, any calendar events you create, including titles, descriptions, start and end times, and associated event details, are stored. If you connect your Google Calendar, we access and store events from your Google Calendar as authorized by you.
  • AI Interactions: Conversations with "Zero", our AI assistant (powered by Groq API), are processed to understand your commands and manage your calendar. These queries are sent to Groq for processing. We do not permanently store the content of these conversations, other than what is necessary to create or modify calendar events as per your instruction.

2.2. Information Collected Automatically

We do not currently collect information automatically through cookies or similar tracking technologies for analytics or advertising purposes beyond what is essential for the functioning of the authentication and session management.

2.3. Information from Google Calendar Integration

If you choose to connect your Google Calendar account, we will request permission to access your calendar data. This includes reading your calendar events, creating new events, and modifying existing events, as necessary to provide the synchronization feature. We will store Google OAuth access and refresh tokens securely to maintain this connection. You can revoke this access at any time through your Google account settings or within our application.

3. How We Use Your Information

We use the information we collect or receive:

  • To provide and manage the Service: This includes creating and managing your user account, providing calendar functionalities, and enabling AI assistant features.
  • To synchronize with Google Calendar: If authorized by you, to perform bidirectional synchronization of your calendar events between our Service and your Google Calendar.
  • To maintain and improve the Service: We may use aggregated and anonymized data to understand usage patterns and improve the functionality and user experience of our Service.
  • To ensure security: To protect our Service and users from fraudulent or unauthorized activity.
  • To communicate with you: We may use your email address to send you important service-related notices, updates, or security alerts. We will not send marketing communications without your explicit consent.

4. Data Usage Limitation for Google Workspace API Data

Zero Calendar's use and transfer to any other app of information received from Google APIs will adhere to the Google API Services User Data Policy, including the Limited Use requirements.

Notwithstanding anything else in this Privacy Policy, if you provide the App access to your Google Calendar data, the App's use of that data will be subject to these additional restrictions:

  • The App will only use access to read, write, modify, or control Google Calendar data to provide the calendar synchronization and management features as described, and will not transfer this calendar data to others unless doing so is necessary to provide or improve these features, comply with applicable law, or as part of a merger, acquisition, or sale of assets.
  • The App will not use this Google Calendar data for serving advertisements.
  • The App will not use any data obtained through Google Workspace APIs (including Google Calendar data) to develop, improve, or train generalized artificial intelligence (AI) and/or machine learning (ML) models.

5. Information Sharing and Disclosure

We do not sell your Personal Information. We may share your information with third-party vendors, service providers, contractors, or agents who perform services for us or on our behalf and require access to such information to do that work. Examples include:

  • Cloud Hosting: Our application and database (Upstash Redis) are hosted on cloud infrastructure.
  • AI Processing: Calendar queries made to our AI assistant "Zero" are processed by Groq Inc. via their API. Groq's use of data is governed by their privacy policy. We only send the necessary query text for processing.
  • Google LLC: For Google Sign-In and Google Calendar synchronization, data is shared with Google as necessary for these services to function, governed by Google's Privacy Policy.

We may also disclose your information where we are legally required to do so in order to comply with applicable law, governmental requests, a judicial proceeding, court order, or legal process, such as in response to a court order or a subpoena.

6. Data Storage and Security

Your Personal Information, including account details and calendar data, is stored in a Redis database provided by Upstash Inc. We implement a variety of security measures to maintain the safety of your Personal Information, including:

  • Secure data transmission using HTTPS/TLS.
  • Authentication using JSON Web Tokens (JWTs).
  • Secure storage of Google OAuth tokens.

While we strive to use commercially acceptable means to protect your Personal Information, we cannot guarantee its absolute security.

7. Your Data Rights

You have certain rights regarding your Personal Information, subject to local data protection laws. These may include the right to:

  • Access: You can view and access your account information and calendar data directly within the Service.
  • Rectification: You can modify your calendar events and some account information through the Service.
  • Erasure: You can delete your account and associated calendar data. Please contact us if you wish to do so. Upon account deletion, your data is removed from our active databases.
  • Data Portability: You can export your calendar data by utilizing the Google Calendar sync feature, which effectively allows you to retrieve your data in a standard format via your Google Calendar.
  • Revoke Consent: You can revoke Google Calendar access at any time through your Google account settings or by disconnecting the integration within our application.

8. Open Source Transparency

Zero Calendar is an open-source project licensed under the GNU General Public License v3.0 (GPL v3). The complete source code is available for review on GitHub at github.com/Zero-Calendar/zero-calendar. This transparency allows you to inspect how we handle data and implement our privacy and security practices.

9. Changes to This Privacy Policy

We may update this privacy policy from time to time. The updated version will be indicated by an updated "Last updated" date and the updated version will be effective as soon as it is accessible. If we make material changes to this privacy policy, we may notify you either by prominently posting a notice of such changes or by directly sending you a notification. We encourage you to review this privacy policy frequently to be informed of how we are protecting your information.

10. Contact Us

If you have questions or comments about this policy, or wish to exercise your data rights, you may contact us at [email protected].