Custom fields are specific to Teamup Calendar. iCalendar feeds - which are a global standard for calendar data sharing - do not support Teamup's custom fields.
If you are using our outgoing iCalendar feed functionality to show Teamup events in another calendar system, any Teamup custom event fields will not be displayed the same way they are in your Teamup calendar.
Some standard event fields (such as Who and Where) may carry over to other calendar systems as expected.
All custom field values will be appended to the description of an event.
The original Teamup event:
The "Pick up location" field is the built-in Where field, renamed. Note below that the Where field contents carry over to the Location section of the Apple Cal event.
The same event, synced via iCal feed, viewed in Apple Cal:
So a Teamup event in another calendar (e.g. Apple Cal, Outlook, Google Cal, etc.) would have the event description (if there is one) followed by 'Event field name: event field value'. Each event in the other non-Teamup calendaring system will also have a link back to the event. Users can click the link to open the original event and see the custom field displayed there.
Note that it is possible to set up an iCalendar feed from one Teamup Calendar to another Teamup Calendar and have custom fields carry over.