With the Apple Watch hitting the market April 24th, developers are rushing to get their apps ready in time, including the big airline companies. Each airline wants to make it as easy and care-free as possible to fly with them. As a frequent flyer myself, I will welcome any innovations that alleviate even a fraction of the stress of frantic air travel. Let's take a look at the new apps underway from American, British Airways, Delta, and United Airlines. Rumor is, they plan to make the most of the smartwatch's at-a-glance display.