CalendarTask 1.53 for Mac was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The program is categorized as Productivity Tools. This free software for Mac OS X is an intellectual property of Xiaowei Cloud, Inc. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe.
From the developer:
CalendarTask is a multi-terminal synchronization, calendar view, schedule management, task reminder, and teamwork application. You can synchronize your schedule in real time between computers and mobile phones. If you are a small team, you can also achieve team collaboration.
You may want to check out more Mac applications, such as ThinkingRock, DesktopCalendar or QuickNote, which might be related to CalendarTask.