In the never-ending quest to make boarding as efficient as possible, Delta Air Lines has rolled out an updated ... and newly issued boarding passes should reflect the updated numbering scheme.

Forbes said Delta uses biometric boarding instead of a boarding pass for more than 90% of international departures across its network. Many other airlines in the U.S. and abroad use biometric ...

Most airlines, and pretty much all legacy carriers (for example United, Delta, and American) have iPhone apps that allow you to check in and digitally retrieve your boarding pass on your phone.