Book a domestic flight on any of the Big Three U.S. airlines, and you won't be sure whether the seat in front of you has a screen. Some do, while most don't. Eventually, perhaps none will.

The proliferation of iPhones, iPads and Android devices, in tandem with increasingly reliable in-flight Wi-Fi, has led to a profound shift by many airlines, which now view entertainment on shorter flights as best delivered wirelessly, without the expense or hassles posed by screens.

As with most things on an airplane, the determining factor is weight. Planting a screen in each seat adds pounds, which burns additional fuel. On top of that, the screens have a tendency to break as people poke and punch them — often to the annoyance of the passenger in front of them.

Today, the new kid on the block for in-flight entertainment, or IFE, is personal-device entertainment — the ability to stream TV and movies to passenger gadgets from a server on the plane. This video is typically free, although United still charges as much as $7.99 to watch live television channels on planes equipped with DirecTV.

"For domestic flights, I really do see the industry trending toward streaming IFE," said Jason Rabinowitz, director of airline research at Routehappy. "It's cheap for airlines to install, there's no wiring, no weight penalty. These systems can be installed virtually overnight, and the costs to maintain these things are virtually nothing."

Avoiding obsolescence

The airlines ask: Why install seatback monitors that will be obsolete in a few years?

Only two national U.S. airlines, JetBlue Airways and Virgin America (neither of which serves Minneapolis-St. Paul), still have seatback screens on all of their aircraft. The rest have a mix of both options. Southwest Airlines deployed streaming content in 2009 and has never purchased a seat with a video screen. "What we really wanted to do was stay away from the seat screen, even back then," said Tara Bamburg, Southwest's manager of mobility, in-flight entertainment and Wi-Fi. "We foresaw as much as anyone could that customers are going to continue to travel with their devices."

The largest carrier, American Airlines, surprised many in the industry when it recently decided to forgo video screens on 100 new Boeing 737 Max airplanes. American said more than 90 percent of its customers carry a device when they fly, so it just made sense. American also hinted that its future single-aisle aircraft will omit video screens, even though it has 40 Airbus A321s and 737s already in the pipeline that will still have them.

"Those phones and tablets are continually upgraded, they're easy to use, and most importantly they are the technology that our customers have chosen," the airline said in an internal note. "So it makes sense for American to focus on giving customers the best entertainment and fast connection options rather than installing seatback monitors that will be obsolete within a few years."

And before you even ask, yes: Airlines are also rushing to add power outlets at each seat. American said half of its domestic planes will be so equipped by the end of next year, rising to more than 85 percent by 2021. The juice will be critical as people spend more time surfing, watching movies or both — either on the same device or multiple devices. That sort of terrestrial behavior is rapidly migrating onto airplanes, said Jamie Perry, JetBlue's vice president of marketing.

"I watched a basketball game on the screen while doing some work on my laptop while listening to music on my phone," Perry said, describing his routine on a recent JetBlue flight. The airline has said it regularly sees more devices connected to its satellite-based ViaSat Wi-Fi service than the number of passengers on some flights. In June, American selected ViaSat for broadband Wi-Fi on the screenless 737 Max airplanes.

Perry said there are 10 to 12 major annual events, such as the Super Bowl or Academy Awards, that make live television "vital" for people who are flying. "There is destination TV, and it doesn't matter how many Hollywood movies you have," he said.

Delta hangs on

Among the legacy carriers, Delta Air Lines has been the largest champion of domestic video screens, including those it is putting on its new Airbus A321s and Boeing 737-900ERs. But the airline has declined to add screens on shorter-haul MD-80s, MD-90s and Boeing 717s. It hasn't decided if its new Bombardier CS100s will be equipped with video screens when those begin arriving next year, spokeswoman Catherine Sirna said in an e-mail. "Delta is choosing to invest in seatback entertainment in addition to the ability to access content via mobile devices onboard while competitors remove options," she wrote.

United Continental Holdings has seatback video on 221 older Boeing 737s and two dozen 757s, about one-third of its mainline fleet. All of its new planes being flown domestically, including the 737-900ER, skip screens in favor of streaming. "We're just seeing the way customers are traveling, and they prefer to use their phone, they prefer to use their iPads, they prefer to use their laptops," United spokesman Jonathan Guerin said.

For the long-haul warriors worried about their next 15-hour flight to Hong Kong, calm down: Contrary to domestic flying, international fleets retain seat screens as a staple, due to longer flights. Meal service requires the tray space on which your device often sits and many airlines consider their customized video offerings an integral part of their passenger experience. So leave the spare charger at home.