Many app creators find the Calendar section very useful. Sometimes it is even the main section of some apps. Here are some examples of use. 

Calendar sections for a employee communication app 

The company Dali Corp decided to use the Calendar section for two major purposes: to communicate about internal company events such as workshops, afterworks or even open days of the company.
A second Calendar section was created to share the company's road map with employees, so that everyone knows the company's current and future projects and deadlines.