The halo view opens a popup with all relevant information on a contact:
addresses, E-Mail addresses, phone numbers
your current correspondence with this contact
shared appointments with this contact
How to display a contact in the halo view:
Depending on the app, use one of the following methods:
Select an E-Mail in the E-Mail app. Click on a recipient or the sender in the display area.
Select an appointment or a task in the Calendar oder Tasks app. Click on a participant in the display area or in the popup.
To close the halo view, click on
in the popup.