What an earlier poster said its true that the pilot gets the flying time or gate to gate time off the Flight Management System.

When the aircraft has Airshow I turn it on at the gate and while we're taxing to the runway it shows Distance to Desitnation, Estimated Time of Arrival and Time to Destination. All of this information is relayed from the Flight Management System. All Airshow is doing is translating the information from the Flight Management System into data that is easy to decipher for the passenger.

If the Flight Management System is setup for a destination using the Metric System Airshow knows from the airport data entered what to display.

Airshow also has other features that activate automatically such as when the pilot turns on and off the fasten seatbelt Airshow can automatically display the Fasten Seatbelt Message.

When the plane is on the intiial descent Airshow knows to display" We will soon be landing in San Francisco . Thank You For Flying United Airlines. Then getting the latest information from the Flight Management System it will display the connecting gate information.

As I recall in an Inflight Guide on an airline under the Inflight Entertainment Map Feature it said that Arrival Information is updated at the pilot's request and to check the monitors in the terminal for the latest updated information.

I think there is also some way to program Airshow to display the Take Off Runway, Estimated Taxi time to Active Runway or Gate. Possibly there is a way to add the Estimated wait time at Customs for Citizens and Foreigners as well as Estimated Connection Time etc and any weather delays etc.

So yes the Flight Management system is the heart of the information.