For trips where you are the Trip Owner, select to set the Trip Mood and Comment visible to other members tracking the trip.  For Trip Trackers, based on the Sharing Options, select the same icon to post a comment to the trip owner.  Comments posted by trackers are not visible to other trackers; only the trip owner.

Trip Mood:	The Trip Mood is set by the Trip Owner and is visible to other members tracking the trip.  It is a fun way to express how you are feeling about the trip and share it with others.  Each mood setting is accompanied by a Mood Icon.
Trip Comment:	The Trip Comment is set by the Trip Owner and is visible to other members tracking the trip.  The comment provides a way to notify others of how the trip is progressing.
Notification:	For the Trip Owner, once you have made changes to the Trip Mood or Trip Comment, you may send an email notification to all members tracking the trip.  Emails are sent based on the 'Email on Updates' settings for Trip Sharing.
Message Indicators:	Available to the trip owner, select the message indicator (New Messages) or (No New Messages) to view the messages History.  When selecting the 'New Messages' indicator, it will reset to 'No New Messages'.