Add Admin module (or banner/icon) that will create a generic notification (for release notes, announcements, etc.). This will display and show notifications on desktops and mobile devices.
With banner, user can:
Close module/banner (message disappears but will show again at next logon until expired)
View details (link should open in separate tab)
Check a check box "Don't show again" which once checked user will not be shown again, until next notification
With banner, user can: