Presence management is an aspect of instant messaging, but also of separate applications such as Twitter. The main question of presence management is "Are you available for real-time collaboration". The wider question "What are you doing? And when did you do what?" that result from this question are asked by timesheet software applications.

For distributed collaboration presence management is a neccessary precondition and you have no other way of indicating business in order to prevent interruptions by phone calls or instant messaging chats and no way of preventing callers calling team members who are currently not reachable.