What’s the “right” aspect ratio for a phone or tablet? Apple and Amazon have two very different ideas about that, as I indicated in an answer on Quora last night. iPads have a 4:3 (1.33:1) aspect ratio, which is great for displaying 8.5″ x 11″ pages in their proper proportion (albeit usually smaller than that actual physical size). It also feels like a more “natural” shape for reading text that wraps to fit, like in an EPUB or Kindle ebook. However, the Fire (and many plain-vanilla Android tablets) has a 16:9 screen for better viewing of the video content Amazon wants to sell to Fire owners—and if the screen is thinner than an 8.5″ x 11″ sheet of paper, it just means Kindle ebook text wraps differently but still fills the whole screen.

Who is “right”? Well, neither one, really. Or, rather, they’re both “right” for their respective purposes. Widescreen video will have black bars (letterboxing) on the iPad; 8.5″ x 11″ PDFs will have black bars on the Fire—but in both cases, viewing that kind of media isn’t what that particular tablet was mainly meant for.

Aspects of Ratio

Aspect ratio has been much on my mind lately. Some television shows I watch have started using wider aspect ratios than the usual 16:9 (1.78:1) of television—going all the way to 2.39:1 “Cinemascope” ratio for Star Trek: Discovery. And a new giant robot show I’m very fond of, gen:LOCK, is also just about that wide. Besides that, many of the most cinematic movies made in the last 65 years have been in Cinemascope ratio (or wider), because movie studios wanted that panoramic view to draw people away from their TVs. So, there’s plenty of video content that’s even wider than 16:9.

In the days of standard-definition television, that wasn’t a huge issue, except to cinemaphiles who were angry that it was standard practice to lop the sides off of widescreen movies in a process called “pan-and-scan” when they presented them on 4:3 television. But when anamorphic DVDs and widescreen HDTV came along, and as consumers got used to seeing letterbox black bars on even wider content, the practice of pan-and-scanning movies fell out of vogue (except in certain streaming video services). Most people now fully understand why wider movies have black bars, and the black bars don’t have to be so thick now that screen shapes are wider in general. And television and tablet screens are big enough that even when some screen space is wasted in showing wider-than-usual content, the remaining picture is still usually big enough to see clearly and enjoy.

And 16:9 seems to be wide enough for most viewers, even considering all the wider content available. A few years ago manufacturers tried introducing 21:9 (2.33:1) televisions, shaped to fit Cinemascope movies, but they failed to take hold in the market. They might have been great for wider-screen movies, but a television was still mainly going to be used for 16:9 TV shows, which meant the extra space on the sides would be wasted most of the time. You can’t find a new 21:9 TV anymore, though there are a few 21:9 computer monitors available.

But then we come to the question of smartphone screens.

When Smartphones Go Wide

If you are reading this on a smartphone, or can, try watching the following on your phone.

If you’re one of the majority of people who has a 16:9 phone (and though it started out 4:3, even the iPhone has been 16:9 since the iPhone 5), you may notice black bars at the top and bottom, representing a portion of the screen that isn’t being used—and, hence, the picture is that much smaller, on a screen that’s pretty small already.

Wider-than-16:9 TVs failed because watching TV was still the main thing they were used for—but smartphones have a lot of other uses, and the aspect ratio may not even matter much for most of them. If making a phone wider doesn’t hurt those other uses (very much), but wastes less of the screen when watching a wider picture, why not? Consequently, some phones have been stretched to 18:9—not Cinemascope, and there will be black bars to left and right when watching 16:9 content, but at least the bars above and below for wider-screen TV will be narrower.

But I’ve just encountered reviews for a couple of smartphones—the Sony Xperia 4 and the Motorola One Vision—that go all the way to 21:9 themselves, meaning that their screens are shaped to fit widescreen content just like the gen:LOCK video above and any narrower videos will have black bars to either side. But who are these devices meant for, and who will actually use them?

How Might 21:9 Affect Smartphone Usage?

As I’ve already noted, there are plenty of Cinemascope-width movies available—65 years’ worth of them, in fact, starting with early spectacles like Oklahoma! (which was actually filmed twice, take by take, in two different incompatible widescreen systems!) and going up through Avengers: Endgame and beyond. Not all widescreen movies were made that wide—plenty of movies are just 1.85:1, which fits on a 16:9 TV with nearly no cropping at all—but the ones intended as major spectacles usually are as wide as possible. These movies can be streamed from various online video services, which mostly know better than to chop them down to fit a 1.78:1 screen. And there are also a handful of extra-wide television shows as well.

If you’re going to watch extra-wide content on a screen that small, certainly going wide physically is the way to do it. The picture doesn’t lose any height, which means it doesn’t get smaller than the screen. Even narrower programs just lose area to the left and right; they don’t have the people on the screen get smaller. On a screen that’s small, that’s important.

But how does it affect the things one might do with a phone in portrait mode? While I haven’t had the opportunity to examine such a phone myself in person, I imagine that they wouldn’t be all that much changed. The big one for people here would be reading ebooks, of course (and email, news, digital magazines, etc.). While people might prefer wider screens to read from, there’s nothing about a narrow screen that’s necessarily unreadable. Indeed, newspapers and magazines have been using narrow columns for some time. You’d still be able to fit plenty of words in.

Web browsing might be a bit more awkward with an even narrower screen—but then, plenty of sites already use simplified mobile versions for phone browsers. And it also depends on how wide the phone is; if the phone stays the same width as shorter phones but just gets taller, you wouldn’t actually be losing screen width; you’d just be getting more scroll room on the screen. The reviewer of the Sony did note that at least one mobile game he plays didn’t deal well with the wider aspect ratio, so that might be an issue with some apps developed for more traditional screen shapes.

A 21:9 phone might be a little awkward to use physically. The Sony reviewer noted the Xperia’s narrower portrait-mode shape made it easier to hold, but harder to reach the top and bottom of the screen one-handed, though there was a mode to shrink the visible screen down so it could be used one-handed.

What Good is a Cinemascope Smartphone?

But what are people really going to want to do with a 21:9 phone? The vast majority of Cinemascope content are feature-length movies—things that traditionally call for extended, immersive viewing at full length. Most people who would care about watching a whole movie would probably want to do it on a screen bigger than a phone.

Phones are more commonly used for much shorter stretches, at times when you need something to occupy you while you wait or do something else. While you certainly could pull out your phone, plug in or link up earphones, and watch five minutes of Doctor Strange while you stand in line at the grocery store or go to the bathroom, you’re far likelier to check your email or social media for that length of time, or even read a few pages in an ebook. Even if you’re watching a video over lunch break or on a public transit commute, you’re probably going to prefer a half-hour or hour-long episodic TV show, and there just aren’t that many of those in the kind of extreme-widescreen you’d want a 21:9 phone for yet.

So, a 21:9 phone would be a little more awkward to use, possibly incompatible with some games, and probably pricier. It might be more difficult to fit in a pocket or purse, too. Is anyone really going to want to buy a phone for the main purpose of watching extra-wide movies, when extended movie-watching is really better-suited to a larger screen?

(Well, I suppose there will always be at least some people interested in any new gadget format. Heck, if the phone were going to be available in the USA, and I knew it would be compatible with Project Fi, I might be interested. But will there be enough? Or would this just be another “early adopter” thing like the pre-Kindle ebook market?)

To be honest, I don’t really know. Some of it depends on just how popular producing television shows in Cinemascope ratio gets in years to come. Are we going to see a flood of extra-wide short-form content now that Star Trek: Discovery—the “most popular streaming show in the world”—has shown how good it can look for a sufficiently cinematic concept? That remains to be seen. Even if there is eventually ample shorter content to watch on such a wide screen, are people going to deem it worth the added inconvenience (and, potentially, price) for smartphones with such a limited use case? Are more manufacturers going to think it’s worth making phones that wide for those people to buy?

(And for that matter, if more widescreen shows become popular, might we see 21:9 TVs take another spin at the market now that 4K high-definition is a thing? That would be interesting.)

In any case, this is largely unfounded speculation based on early hints. Perhaps Cinemascope television will remain a flash in the pan—and, very possibly, so might 21:9 smartphones. In any case, it will be fun to see what happens.