Lightcal privacy policy
Last updated: 1 November 2026
Lightcal is a free, open-source calendar for the Windows tray, made by Radik Ilin (Koona). This policy says what the Lightcal app does with your data, in particular the calendar data it reads from Google and Microsoft when you connect an account. The source code is public, so every statement here can be checked.
In short
- Lightcal has no account, no server and no telemetry. Koona never receives your calendar data, your sign-in or anything about how you use the app.
- It only reads calendars. It never creates, changes or deletes an event.
- Your data goes only between your computer and the service you connected: Google, Microsoft or the host of an ICS link.
What Lightcal reads
Only what you connect, and only after you sign in and agree in your own browser:
- Google Calendar, with two read-only permissions: the list of your calendars (
calendar.calendarlist.readonly) and their events (calendar.events.readonly). - Outlook and Microsoft 365, through Microsoft Graph, with the read-only
Calendars.Readpermission, plusoffline_accessso that the app stays signed in. - A private ICS link that you paste in, downloaded over HTTPS.
From these it reads the names and colours of your calendars and, for the calendars you choose to show, the events: title, time, location, calendar and the link to the event in the web calendar. It does not ask for your email, contacts, files or any other data.
How it uses that data
Only to show your calendars in the app: the dots under the days, the agenda and the details of an event. Calendar data is not used for advertising, is not sold, is not used to train AI models, and is not used for anything other than showing it to you.
Where it is kept
On your computer only. Lightcal keeps the events it reads in memory while it runs. On disk, in your Windows user profile, it keeps its settings, including which calendars you chose to show, and the sign-in tokens and ICS addresses, encrypted with Windows data protection (DPAPI) for your user account. Nothing is copied to Koona or to anyone else.
Sharing
Lightcal shares your data with no one. It talks only to Google (googleapis.com) or Microsoft (login.microsoftonline.com, graph.microsoft.com) for the account you connected, to the host of an ICS link you added, and to GitHub when you check for updates. The update check asks GitHub for the latest Lightcal release and sends no calendar data. Links such as Open, koona.app or Sponsor open in your browser only when you click them.
Google user data
Lightcal’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. Data from Google stays on your computer, is used only to show you your own calendars, and no person reads it.
Removing your data
In Lightcal, open Settings, then Accounts, and disconnect the account or remove the ICS link: the app deletes its tokens and the address from your computer. Uninstalling Lightcal removes the app; its settings folder can also be deleted by hand. To withdraw the permission on the provider’s side as well, remove Lightcal in your Google account’s third-party connections or in your Microsoft account’s app permissions. Disconnecting never deletes anything from your Google or Microsoft calendar.
Children
Lightcal is a general-purpose tool and does not knowingly collect any data from anyone, children included.
Changes
If Lightcal starts handling data differently, this page changes first, with a new date at the top.
Contact
Questions about this policy: support@koona.app, or an issue on GitHub. See also the koona.app privacy policy for this website.