The current Google Account is displayed at the top of the Inbox.
If you have more than one account, you can switch accounts to view
the messages in each Inbox. Simply tap the Accounts & labels icon 
at the top left
corner to select another account or label to display.
Conversations with new messages are displayed with bold subject
lines. To read a message in a conversation, tap its subject line text.
indicates
that you were copied on this message.
indicates
that this message was sent directly to you.