Apple (AAPL 0.64%) shares fell nearly 4% on Thursday on reports of bending iPhone 6 Plus devices. The sell-off shaved about $20 billion off the company's market capitalization. But Apple's rapid public relations response to the issue calmed nerves, and shares rose about 3% on Friday. With both sides of the story out, should investors be concerned or not?

Image source: Apple.

iPhone 6 bending goes viral
Apple's 5.5-inch iPhone 6 Plus not only sports a large phablet-sized display, but it is also thinner than the smaller four-inch iPhone 5s that it launched in 2013. Given how thin Apple's first foray into the phablet category is, it's not surprising that, when a video of the device bending was published on YouTube, it quickly went viral.

On Tuesday, MacRumors said "a small but growing number of iPhone 6 Plus owners have reportedly bent their phones after carrying the device in their pockets just days after launch." One anecdote of the 6 Plus bending in MacRumors' forums described a simple day of "dancing, dining, and driving to a wedding," MacRumors' Kelly Hogkins said. 

A combination of bending iPhone 6 reports in forums and videos had the Street worried. But is the issue really worth fretting about?

Image source: Apple.

Apple speaks up
Adding some perspective to the issue, Apple said in a statement provided to a number of media outlets on Thursday that the iPhone 6 bending is "extremely rare." In fact, Apple said only nine users had complained of the iPhone 6 bending. Nine pales in comparison to the more than 10 million iPhone 6 units sold by the company before Monday, during its three-day launch weekend. Further, the company said in its statement on the bending concern that the iPhone 6 devices undergo rigorous testing for durability, "including 3-point bending, pressure point cycling, sit, torsion, and user studies."

Despite the complaints, Apple refuses to admit any quality issues: "iPhone 6 and iPhone 6 Plus meet or exceed all of our high quality standards to endure everyday, real life use." To drive home its point, Apple even invited journalists to a rarely seen facility where it puts its devices through pressure tests, where journalists saw the iPhone 6 torturing firsthand.

"The idea is to give the phones a lifetime of testing, but without spending a lifetime doing it," noted Josh Lowensohn from The Verge, who witnessed the testing facility. "The machines that do this methodically set various pads and pressures on the phones over and over again with only a small hiss of air and a dull 'thunk' noise."

iPhone 6 display. Image source: Apple.

Apple had tested 15,000 iPhone 6 devices and 15,000 iPhone 6 Plus devices, Apple's senior vice president of hardware engineering Dan Riccio told The Verge. "As we add more and more features, we have to find out a way to break them before customers do," Riccio said.

Apple's confidence, statistics, and willingness to make bold statements about the durability of the iPhone 6 devices in light of the viral video of a bending iPhone 6 Plus suggest that the concern was likely blown out of proportion. Unless further evidence arises against Apple's argument for the durability of the new iPhone models, investors and consumers shouldn't give the issue any weight.