MonoCalendar is a calendar software that lets you have as many calendars as you would like, each one with different names and colors that you choose. It has an attractive interface and it displays all your appointments whatever calendar they belong to. But the appointments that belong to the calendar you are currently viewing will be less transparent than the others that belong to other calendars. You can add and edit appointments and can drag and drop them to move. You can even import and export calendars. It gives you easy navigation facility to move forth and back through months and years.