- I would go with Google Calendar. 1. create a secondary calendar for e.g "Team Calendar" in your Google Calendar. 2. Share it with required people. 3. All team members with whom this calendar is shared can select items in this calendar to be displayed in their calendar. 4. Now whenever you create any item on this shared calendar, all members can see that in their own calendar. If you are using G Suite (business version of Gmail/calendar etc), you can also leverage "Resource Calendars" to compliment your team calendar.
- You could try Agile CRM's calendar feature (https://www.agilecrm.com/calendar) with which you can create, manage and track events & tasks. Furthermore, you can share your calendar with ical, schedule activities, keep track of notes, set priority, check in-progress status, manage tasks, sync with Google calendar, schedule your appointments.