There's a Lite version which is free. Of course, the Pro version adds many more features, such as 2-way Google Calendar sync, email/SMS reminders, calendar sharing over a local network, calendar publishing to the web, a List view, and more. However, for many people, the Lite version is more than sufficient for their needs.
In any case, I hope you'll enjoy the free Pro version and will find it useful.
VueMinder Calendar Pro
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