An Exclusive Look at Reliability Labs, Where Google Stress-Tests Pixel Hardware

Smartphones are durable, powerful devices we carry everywhere. They get slightly better every year, too. Whether that's through improved glass technology that's more shatter- and scratch-proof, or screen size adjustments to ensure the best experience in your hand.

Take the just-announced Pixel 10 Pro Fold, for example. It's now IP68-rated for water and dust resistance, just like most flagship candybar phones. Just a few years ago, the hinge mechanism on folding phones was still having problems with dust, and even Samsung's latest Galaxy Z Fold7 is only IP48, meaning it's not as dust-proof as the Pixel.

Phone manufacturers run a battery of tests on their devices constantly throughout the development cycle—sometimes more than a year before the product even comes out. Google invited me to its headquarters in Mountain View, California, to check out one such testing center, dubbed Reliability Labs. It's a nondescript building on Google's campus, but inside are next-gen Pixel phones and smartwatches getting tumbled, dropped, and even frozen to measure their overall durability. (Google paid for a portion of my travel expenses to see its research facility.)

The Folding Test

You've probably seen a test just like this with other folding smartphones. The Pixel 10 Pro Fold is clamped to this machine, which continuously folds and unfolds the device, and it's what allows phone makers to say their device can withstand 250,000 or 500,000 folds, offering a little more peace of mind for the hinge's reliability. This is just one testing machine, but Google says it has multiple of these operating in Asia, folding and unfolding preproduction units.

Google claims the new Pixel 10 Pro Fold can withstand 10+ years of folding, or 200,000 folds for the hinge. Samsung claims 500,000 folds for the Galaxy Z Fold7. (If you fold the phone 100 times a day—which is on the excessive end—that's 365,000 folds after 10 years.) But Google's 10+ years claim isn't just about the hinge. The new gearless design of the Pixel 10 Pro Fold allows for more room for the display to flex, putting less strain on the screen, and there are several new strengthening layers to support the display. That means both the display and hinge should last a decade.

Scratch and Wear Tests

Next up are a few wear tests. The first was a mannequin's arm wearing the Pixel Watch 4, bolted to a robot arm that moved back and forth. The watch's band was resting on a piece of wood, and the test measured how well the strap fared when rubbing against the material. (It's easy to switch the material it rubs against to something else, like a metal sheet.) It's a surface abrasion test Google runs to test new strap types for its smartwatches; a pressure sensor applies consistent force for accurate measurements.

There aren't any fresh strap materials for the new Pixel Watch 4, but this is one of the processes used to test various materials used for the bands. I asked the company about recent studies that show fluroelastomer straps—like the ones Google, Samsung, and Apple sell for their respective smartwatches—have high concentrations of “forever chemicals,” though there's limited knowledge on how much they're absorbed by the skin. Francis Hoe, senior product manager for the Pixel Watch, says Google runs several biocompatibility tests before releasing any kind of product, and is “always thinking about new materials,” though he didn't share any other details.

In the next room, there's a tray with several generations of Pixel phones inside (including the latest Pixel 10 series), lying face down on another wooden surface. This is designed to mimic a real-world user sliding their phone face down on a table. Google's testing team runs these tests for certain intervals, like 30 minutes, and then checks for scratches. It offers an accelerated look at how the cover glass will fare over a long period, on different surface types, and how it compares to previous generations. (The Pixel 10 series uses the same Gorilla Glass Victus 2 material as its predecessor.)

The Tumble Test

How does a phone fare when thrown into a bag or purse filled with other stuff? Yes, people actually toss their pricey phone into a bag, but that can scratch up the glass. This is what the tumble test monitors. This small, red tumbler is filled with a handful of common items, from a hairbrush and a nail clipper to keys and pens. A team member popped in a Pixel Watch 4 in one machine, and a Pixel 10 Pro in another. Just like your dryer, everything tumbles together for a certain number of cycles, after which Google's team will check the hardware for damage and rinse and repeat. This allows Google to monitor the overall durability and scratch-resistance of the devices, from the glass to the buttons and the anodized metal.

The list of items in the tumbler stays consistent year over year, allowing for direct comparisons over prior generation hardware. Hoe says these kinds of tests begin early on in development, and Google then uses reliability results to inform key decisions at the next checkpoint of the development phase.

Shock Tower

Arguably the loudest test I experienced, Shock Tower is what Google calls this contraption. Think of it like a drop tower ride at an amusement park that plummets you instantly from a great height (leaving you with soiled pants). Shock Tower is a controlled drop test—a Pixel 10 was clamped on and dropped at a specific speed and height, with a loud CLANG when it hits the bottom.

It doesn't necessarily measure how the drop affects the external parts of the phone, like the glass or display—though I was offered safety glasses just in case the glass cracked (it didn't). Instead, it's more to help monitor how the shock affects internal components, and allows Google to bring these components to failure to see how the assembly of these sub-modules could be affected by drops. You wouldn't want your battery to get disconnected from a drop, and that's something this test could potentially help show.

Drop Test

There is a not-so-controlled drop test, too. Rivaling the Shock Tower for loudness, this 1-meter metal box is kind of like the tumbler machine in that it's constantly rotating 360 degrees. On one side is the Pixel 10 Pro Fold, and on the other, a Pixel Watch 4—both constantly hitting one end and falling in a frenzy to the other as the machine spins. It is a painfully loud sound, and after a few spins, you start to feel sorry for the hardware.

Hoe says Google typically runs this test for several cycles, but it usually involves 100 drops per test, after which the team inspects the hardware to determine if it's a pass or fail. There are different criteria in what determines a pass or fail, but it's not just about checking to see if the glass cracked. Did the buttons break? Did the camera module pop out? Does the phone still turn on? Those are the kinds of things the team looks at.

Freezing and Extreme Heat Test

This room was cramped with machines that helped measure how devices could handle heat and cold, and rapid transitions between extreme temperatures. Naturally, there was a Pixel Watch 4 sitting frozen in a machine that blasted it with water that's rapidly cooled, and another machine ratcheted the temperature from -10 to 35 degrees Celsius (14 to 95 degrees Fahrenheit) at 95 percent humidity levels to monitor the temperature change.

These tests have two purposes. It shows how well the device can continue to perform after enduring these extreme temperatures. However, it also allows Google to simulate the age of the hardware, testing them at different intervals to monitor performance over an accelerated period.

Water Resistance and Pressure Test

Next, I went into a room where I had to wear a poncho to avoid being hit by jets of water. It's the water resistance test! I watched a Pixel 10 Pro Fold get doused in jets of water from all angles, ensuring Google's hardware would pass the IPX5 test. (Google would still need to send its hardware for independent testing to earn the IP68 badge.) The “5” in that number specifically tests for protection from jets of water at any angle, but there are other tests Google conducts, like IPX8 for water immersion. It's just not as interesting to look at—think of a Pixel 10 sitting in a water tank for 30 minutes.

In the next room over, I found several Pixel Watch 4 models sitting in what looked like a pressure cooker. This contraption is what Google uses to measure how much pressure the hardware can withstand, helpful for swimmers and divers. The latest Pixel Watch maintains its 5 ATM rating, meaning it can handle up to 50 meters for a certain length of time. Once the devices are inside and the 5 bars of pressure have been set, air bubbles will surface on the hardware, meaning there's a leak; Google would have to take apart the device to see what's causing the issue.

Empathy Models

The last thing Google showed me revolves around the size of the phone. You'll see two rows of fake devices: the left model on the top is the Pixel 8's actual size, and the left model on the bottom is the Pixel 8 Pro's real-world size. The other slabs approximate what the phone feels like for folks with medium to smaller hands (they're weighted accurately). The middle is what people with medium-sized hands feel when holding the phone, and the right model is what it's like for someone with small hands. I did a little hand measuring test that determined my hand was even bigger than the “large” size, so I'm positively sorry for all the folks with small hands who have to experience these Very Big phones.

It's this kind of test that helps shape sizing decisions for the phones. “We're often trying to make sure our devices are as comfortable for all the people purchasing the product … really trying to understand the critical dimensions,” says Stephanie Scott, group product manager at Google. With this test, folks with large hands on Google's team are able to see what the phone they're designing feels like for smaller paws (hence the “Empathy Models” name for the test). Google did share that its data shows that women tend to gravitate to the smaller phones, and that the Pro models tend to have a male demographic.

Continuous Testing

It's worth noting that these tests run continuously throughout the development cycle. That means when a new prototype version of the hardware is ready, Google saves a few models to go through the battery of tests at Reliability Labs, and that'll happen again with the next version of the hardware. And Google doesn't just do lab tests.

“Reliability helps us prove the robustness of the design, and then we run an internal team testing program, and we test it across all the iterations of the product,” Hoe says. There's a team of real-world users that put the phones and watches through their paces outside of a lab setting.

Google isn't the only company running these kinds of stress tests—every major phone manufacturer likely does similar, if not identical, tests. However, these tests don't guarantee a product will be free of issues once it hits the market.

There are plenty of instances where Google has dealt with hardware issues over the last 9 years of its Pixel phones, from screen issues to even problems with the camera module. More recently, the company's Pixel A-series phones are running into battery problems. Some Pixel 4a, Pixel 6a, and Pixel 7a devices are undergoing a battery performance program where a mandatory software update cuts the battery capacity and reduces charging performance to prevent overheating risks. (Google is providing a free battery replacement or Google Store credit.) I asked Google if these battery woes could affect the latest Pixel 9a, and here's what a Google spokesperson said:

“Google continuously improves Pixel testing based on user feedback and thoroughly investigates reported incidents for all components, including batteries. With Pixel 9a, we delivered the largest and longest-lasting battery of any A-series yet. We’ve been encouraged by its reception so far and are confident in the phone’s longevity and durability.”

We'll have to wait a few years to see how that holds up.