The International Air Transport Association has agreed on a standard bar code that could be sent to passengers' cell phones or smart phones via email or text message. To board, passengers would simply flash their phones to airport officials.

Air Canada last month implemented a similar system for passengers who check in using their cell phones or smart phones. The system, however, is only available to non-U.S. destination flights. Quantas and Virgin Air are also considering going paperless, although no dates for the change have been announced.