Most airlines only inform passengers the flight delays by displaying the 'Delayed' sign on the board displaying flight number, and nothing else.

But some low cost airlines do better. Ryanair informs the causes of flight delay, like ATC delay, weather delay, etc. Jetblue places TV on the borading gates, so to display the real-time situation of the delayed flight.

Can anyone tell more ways the airlines inform the flight delays to passengers?