Should you buy the iPhone 11? The new Apple upgrade rule

We're calling an end to a golden rule of tech: You no longer have to upgrade your iPhone every two years. Three will do just fine.

Apple's $700 iPhone 11 and triple-lens $1,000 11 Pro arrived in stores on Friday. But unless you're the owner of a 2016 iPhone 7 or earlier - or angling for Instagram influencer status - you probably don't need one.

We've been testing the new phones and think they're swell. But so was the iPhone X from two years ago. So we approached this review with a different lens: Instead of comparing it to last year's iPhone XS, we've been using the 11 alongside iPhones that are two and three years old - the X and the 7. To measure the most important change, the cameras, we used a three-way selfie stick to make all the phones snap the same photo at the same time.

We were</ard-pressed to find features we couldn't live without on the 11 - and surprised at how well the X has aged. Our takeaway: Anyone with an iPhone 7 (or older) will appreciate that the 11 shoots better photos in the dark, promises a longer battery life and has a larger screen. Otherwise, save your cash for next year, which will likely bring bigger changes like support for ultrafast 5G networks.

Our three-year rule reflects the reality that many people are already holding off. In 2013, Americans bought new smartphones after 20 months, on average, according to research firm Kantar. As of this year, we're waiting 24.2 months.

Where did the two-year cycle come from anyway? In the U.S., phone carriers used to subsidize the cost of new phones with two-year service plans. Apple also used a naming system - 4, 4S, 5, 5S - that suggested big improvements came in two-year cycles.

But the hardware breakthroughs haven't been rolling as fast lately. And Apple itself has made it easier to keep using old iPhones, with software updates for older models and by adding waterproofing and stronger glass. Cheaper battery replacements help, too.

Of course, our rule is just a guide. It's okay to hold on to your iPhone even longer. Apple's latest iOS 13 update supports models going back to the four-year-old iPhone 6S. You might even decide to switch to an Android phone, though most people today are pretty locked in to a platform.

What matters most isn't speeds and specs - or even a flashy third camera. Here's what an iPhone 11 or 11 Pro will actually feel like coming from the iPhone 7 and the iPhone X.

The camera

A picture is worth a thousand words. But is it worth $1,000? Or even $700?

With our test trident shooting cameras simultaneously, we could clearly see improvements in the 11 over the 7 in lighting and color. But vs. the X? The changes are only dramatic in very specific photo situations.

In daytime shots - and even a few we took at happy hour - the 11 produced more detail than the 7 and X. But in some photos, we actually preferred the warmer tone of the X.

In the dark, a new Night Mode on the 11 and 11 Pro made a more dramatic difference, finding light and color in situations that even our eyes couldn't. It will appeal to anyone who has more than 1,000 Instagram followers.

When the Night Mode activates (which happens automatically), the iPhone merges together a bunch of shots taken with different exposure lengths, taking the best, sharpest bits of each. That means you (and your subjects) have to hold really still - up to about 30 seconds - as the iPhone collects all those shots. How long you have to wait depends on how dark your scene is, and how much the iPhone senses your hand is shaking. (Using a tripod or bracing the phone against a wall helps.)

How about composing more interesting photos? The 11 doesn't offer anything new to help with our most practical camera need: zooming closer. The 11 Pro models include a lens with two-times optical zoom, but it's no more powerful than the one already on the X and even the 7 Plus. (We wish Apple had included the zoom lens on the regular 11 model, but it did not.)

So what about the new lens Apple is touting? All of the 11 models include an "ultrawide" lens. Like looking through the peephole in a door, it lets you capture more with a 120-degree field of view. It's a creative tool that can be fun when you're very close to your subject. We're just not sure how often we'll actually make use of it.

Camera aficionados take note: You might want to wait until Oct. 15, when Google is expected to unveil its Pixel 4; last year's model beat the camera competition with a low-light mode called "Night Sight." And we don't yet have a read on the most curious new feature on the 11 Pro: a mode called "Deep Fusion" that promises to produce images with even better texture and tone. It's coming in a software upgrade and wasn't available to test.

Battery life

The 11 promises some tremendous, life-altering battery improvements. But what that means for your upgrade is harder to say.

Apple says the iPhone 11 Pro can go four more hours than last year's iPhone XS before needing a recharge. How about vs. an iPhone 7? It won't say. Apple offers only this consistent data point: While playing a nonstop video, both the 7 and X lasts 13 hours; an 11 lasts 17. But that's hardly a real-life situation.

We'll need more time to verify this claim with our own battery tests. The smart geeks at Tom's Guide report in their own lab that the 11 performed about the same as last year's iPhone XR, lasting 11 hours and 20 minutes of continuous Web surfing over 4G. The larger 11 Pro Max lasted nearly 12 hours.

(If battery life or the device's overall slowness are your main motivating factors for getting a new phone, consider getting your battery replaced before buying a new one.)

Face ID

When Apple skipped the iPhone 9 and jumped into letters with the iPhone X, it also jumped into the future. For anyone coming from a 7, you'll immediately notice:

1. There's no more home button or fingerprint reader. Instead, you swipe up from the bottom of the phone and unlock with your face. Most people get used to it.

2. The fancy face-detecting cameras also do a thing called Animojis, which map your face to let you pretend to be characters such as an octopus or smiling pile of excrement.

On the 11, you get one more feature not available in the X: You can take what Apple is calling a "slofie," or a slow-motion video of your face. You of course could take a slow motion video of your face before using the back-facing camera, but this saves you the effort of rotation. Ah, innovation.

Speed and storage

Apple is beating the pants off the rest of the industry in the speed of the processor that's the brain of the phone.

But we had a hard time feeling it vs. the X. That year hit an inflection point for everyday functions. For example, tapping auto-adjust button in the Photos editing app took one second on a 7, 0.6 seconds on an X and 0.4 seconds on an 11.

There is one major spec upgrade since the 7 that you'll really feel: more storage. An entry-level iPhone 7 only came with 64 gigabytes of storage. The X and 11 both start at 64 gigabytes.

Durability

The iPhone 7 was the first of the line to get waterproofing. The 11 is the first generation you could possibly take snorkeling. The 11 is water resistant up to two meters and the 11 Pro up to four meters. We're not sure that's going to move the ball for many people.

Apple also claims the glass covering the front and back of the 11 is stronger than on the X. We did not attempt throwing our review units on concrete. But we did miss the metal back on the 7, which doesn't shatter. The switch to a glass back on the X and later allows iPhones to charge wirelessly - a tech that still hasn't really caught on everywhere.

Should you go Pro?

So you've decided to upgrade. Which one do you buy?

Anyone on a budget might do just fine with last year's model, the iPhone XR, which now sells for $600. It's got almost everything good about the $700 11, except for Night Mode, that wide-angle lens and this year's even-faster processor. Its battery life is still fantastic. If you've got $100 to spare, Night Mode on the 11 alone is worth it.

But aren't you supposed to buy the "best" iPhone? Apple tries to make that case with the "Pro" name on the priciest models. (Who doesn't want to be a pro?) What you're really buying is that third, zoom lens. It's only available on the Pro and Pro Max.

The rest of the differences between the 11 and 11 Pro models can best be described with the shrug emoji. The Pro offers a slightly better, and brighter, screen. The 6.5-inch Pro Max version is the only way to max out your screen addiction, and also get the longest-lasting battery.

Reasons to buy nothing

There are some legitimate reasons you may want to hold onto your iPhone 7 or older. Mainly: whether you can physically hold onto it.

Apple's phones keep on getting larger. Sure, they need the extra space to cram in all the upgraded technology, but many people, especially those with smaller hands or shallow pockets, still like their phones petite. The iPhone 7 is both thinner and lighter than any phone that came after it. The iPhone SE, now only sold used or refurbished, is the only iPhone with a pocket friendly 4-inch screen.

A $700 and up gadget is a serious investment. There is one bit of math to help you justify an upgrade: The longer you keep your phone, the lower its trade-in value. For example, Apple will only give you up to $150 to trade in an iPhone 7. An iPhone X, however, is worth up to $400 to the company.

If you've just got to be seen walking around with not one, not two, but three camera lenses, we get it. Just promise you'll also donate to charity along with Apple. But you should also feel no pressure at all to buy the shiny new thing - and know you're not alone.