Presence service provides you with a convenient and simple way of sharing your availability with colleagues, family, or friends. You can control and personalize the information you want to share as your current presence status. The presence status includes your availability, status message, and personal logo. Other users who have access to the service and who are requesting your information are able to see your status.
Presence can be used to show your colleagues that you're at a meeting and do not want to be disturbed. Or that you're driving your car and are available by voice contact only because you cannot respond to a text message.
To set up My presence settings you need to access Settings, Chat and my presence settings, and Edit active chat and presence settings. The exact setting varies in respect to which server you need to access and which operator you use.
...how to start 