Dates and times are captured as follows on form entries:
Date only and Time only fields are captured in the local device time, but without any time zone information.
As such these are always displayed as the raw, local time values, without any time zone adjustment.
Date/Time fields are captured with time zone information since they have a complete date and time dataset.
These values are output on the web platform with adjusted time zone based on the logged in user's time zone, or if not set (or if running in a Connector context) then the Organization Setup time zone settings.
Our API mirrors the above, in that date only and time only fields return just raw DD-MM-YYYY or HH:MI:SS values, while Date/Time fields return as ISO 8601 format (i.e. time zone inclusive).
All other date/time values found on our API accept and return ISO 8601 format.