(The video above was part of an April’s Fools joke from the American cinema chain Alamo Drafthouse, but now it seems one step closer to reality.)

It wasn’t that long ago when vertical video, and watching movies on phones at all, was considered taboo. In a video that went viral in 2017, director David Lynch lamented the growing popularity of the practice. “It’s such a sadness that you think you’ve seen a film on your fucking telephone,” Lynch said. Noted film critic Anne Billson once joked that people who watch movies on phones “should be shot.”

But the ubiquity of phones—and, subsequently, of vertical video viewing—is forcing filmmakers to come up with ways to make content that fits how consumers are using the technology. Studies show we hold our phones vertically 94% of the time, while videos watched vertically have a higher completion rate than ones watched horizontally.

So it makes sense mobile apps would orient much of their video content to vertical viewing. A theatrical film released in vertical formats is a different animal entirely. As the film blog Slashfilm pointed out, a World War II movie shot in vertical format is something of an anachronism. The effect of most vertical video is that it looks like someone filmed it using their phone—a device that didn’t exist then, as far as we know.

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