You can find detailed release notes for this release and past releases at Release Notes.
We add a functionality to allow administrators to import observers from a bath file.
We add an option to view these content in a separate browser window. This applies to website or custom activities.
You can now set a course to automatically assign zero score to unsubmitted gradable activities after the activities become past due.
We add a new "Allow users to save" option for custom activities of completion and score set by content (SCO). The new option allows users to save custom activity data proactively with the new "Save", and "Save and Close" buttons in the ActivityPlayer component.
We enhance the Web Services request API to include the user role, the evaluated review setting values, and the evaluated review setting values for custom feedback groups.
We add an option to enrollment completion rules so that enrollments with failing course scores can be set automatically to completion.
We add a new button to allow users to mark enrollment complete from the final grade page. The button will be visible only when users have owner permission on the course.
You can now force users to re-login after a session has been closed unexpectedly in scenarios such as when the connection to the server is lost, or users have logged in with a different credential, or users have logged out from another session.
If you leap-frogged previous releases to upgrade to 2015, you'll probably want to read the following topics to discover features added in the past.