The 5 methods Apple uses to test iPhone durability and bendiness


Tests prior to launch showed the iPhone 6 and 6 Plus could have bending issues.
Photo: Cult of Mac

Today Apple spoke out on Bendgate, the international scandal that has set the world ablaze with questions about the iPhone 6 Plus like, “Will it bend?”

“With normal use a bend in iPhone is extremely rare and through our first six days of sale, a total of nine customers have contacted Apple with a bent iPhone 6 Plus,” said Apple in a statement. To further solidify its stance on not making bendy hardware, the company has laid out the five methods it uses to test iPhone durability.

In a tour of the lab where it performs durability tests, Apple said that it intentionally broke 15,000 iPhone 6 and 6 Plus units. “The iPhone 6 and the iPhone 6 Plus are the most tested,” Dan Riccio, Apple’s senior vice president of hardware engineering, told The Verge. “As we add more and more features, we have to find out a way to break them before customers do.”

According to the The Wall Street Journal, here are the five tests iPhones undergo:

Three-point bending

Photo: The Verge

To make sure new iPhones can handle “reasonable” force, Apple puts pressure on the device at three different points along the frame. An Apple job listing posted today reveals that the company also does 4-point bend and tensile testing.

Pressure-point cycling

Photo: The Verge
Photo: The Verge

The pressure-point cycling tests place “substantial” force across an iPhone’s display and encasing, while it is held along its edges, to ensure that an iPhone can be bent and pushed many times over during its lifespan. Apple runs this test hundreds of times to ensure durability.

Torsion testing

The iPhone is twisted and turned like a piece of licorice about 8,000 times. “The company does this to make sure its devices can handle twists and torque in various situations, such as sitting on an iPhone unevenly.”

Sit tests

This is exactly what it sounds like. An engineer sits down thousands of times with the iPhone pocketed in every position imaginable. What a job.

Recode explains in more detail:

First was the “sit test.” Dan Riccio, Apple’s senior vice president of hardware engineering, says this test is the one that is most relevant for customers with concerns about the phones bending in pockets. There are three parts to the sit test. The first part simulates a typical user sitting down on a hard surface, the second simulates someone sinking into something softer like a couch, and finally there’s what Riccio calls a “worst-case” tests, where someone would have a phone in their pocket and sit down on a hard surface at an angle.

Real-life user studies

Photo: The Verge
Photo: The Verge

Another part of testing involves real humans, hundreds of company employees live with and use the phones in various situations to test for both durability and performance.

“The bottom line is that if you use enough force to bend an iPhone, or any phone, it’s going to deform,” Riccio told The Verge during the tour of the lab.

Here’s Apple’s full statement on Bendgate from earlier today:

Our iPhones are designed, engineered and manufactured to be both beautiful and sturdy. iPhone 6 and iPhone 6 Plus feature a precision engineered unibody enclosure constructed from machining a custom grade of 6000 series anodized aluminum, which is tempered for extra strength. They also feature stainless steel and titanium inserts to reinforce high stress locations and use the strongest glass in the smartphone industry. We chose these high-quality materials and construction very carefully for their strength and durability. We also perform rigorous tests throughout the entire development cycle including 3-point bending, pressure point cycling, sit, torsion, and user studies. iPhone 6 and iPhone 6 Plus meet or exceed all of our high quality standards to endure everyday, real life use.

With normal use a bend in iPhone is extremely rare and through our first six days of sale, a total of nine customers have contacted Apple with a bent iPhone 6 Plus. As with any Apple product, if you have questions please contact Apple.

Even with Apple’s downplaying of the issue, Consumer Reports is undergoing an authoritative test to see if the new iPhones are structurally weak.

A video showing the phones bending under pressure from bare hands suggests that the main point of weakness is around the area near the volume buttons.


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