Salesforce Fact #932 | List of current logged in users

There is an object AuthSession which can be queried to get the list of users currently logged in to the org.

example query: Select id, Users.name, CreatedDate, LoginType, SessionType, IsCurrent from AuthSession

Reference: https://developer.salesforce.com/docs/atlas.en-us.object_reference.meta/object_reference/sforce_api_objects_authsession.htm