Plain Today Calendar is described as 'application provides Notification Center Calendar Widget for your Mac (with additional features)' and is a Calendar in the Office & Productivity category. There are three alternatives to Plain Today Calendar for a variety of platforms, including iPad, iPhone, Mac, Online / Web-based and Sunbird. The best alternative is Google Calendar, which is free. Other great apps like Plain Today Calendar are Apple Calendar (Free) and SSuite My Calendar Diary (Free).
With Google Calendar, its easy to keep track of all your lifes important events in one place. You can add events and send invitations effortlessly, share your schedule with friends and family, and search for events you might enjoy.
Keep track of your busy schedule and share it with others using Calendar. Create separate calendars — one for home, another for school, a third for work, and so on. See all your calendars in a single window or choose to see only the calendars you want.