Status setting1. 4 types of status " 
Online, 
do
not disturb, 
Out, 
Offline
" for your setting depends upon your own working status.
2. You can tell the status for each contact by the icon on the left
side of a contact：
1) 
represents the contact is offline.
2) 
represents the contact is online.
3) 
represents the contact is online but out now.
4) 
represents the contact is online but disturbance is not allowed.