Hi
You can setup custom fields of type date alert to remind you when a service/calibration/maintenance is due for an asset. Once you receive an email for the custom field, the asset can be put in service mode. You can also create and track service tickets from the assets detail page from Items → Assets → Asset details → scroll down to the Service tab and add a service ticket.
At the moment service tickets cannot be added to an external calendar but the correct email alerts can be setup to remind you of the beginning and end of service.

regards
EZOfficeInventory Support