When you arrive at the group location, the record is shown with the Arrive button.
Procedure
On the event record, tap Arrive.
The event is marked Arrived and the time of arrival is displayed in the
event entry in the manifest.
If DriverMate detects that multiple passengers are to be picked up or
dropped off at the same geocoded location, when you mark one trip as
Arrived, it automatically marks all of them as
Arrived.