Is the iPhone 6 Plus really an upgrade or is it more inconvenient than it's worth? The Post's Hayley Tsukayama puts Apple's newest phone to the test. (Jonathan Elker and Hayley Tsukayama/The Washington Post)

Apple's iPhone 6 Plus has been out on the market for only a few days, but scattered reports that the phone's thin, wide frame is bending in users' pockets are popping up on Apple's own customer service forums and on MacRumors.

The new mega-iPhone's larger, skinnier frame might be a bit susceptible to bending, particularly if wedged in tight spots such as pockets. And anecdotes seem to indicate that the bending happens around the volume buttons, where holes are cut into the metal case.

Still, the reports are surprising, given the high marks for durability that the latest iPhones have earned -- an improvement over past Apple devices. Insurer SquareTrade went on record Sunday saying that the iPhone 6 and iPhone 6 Plus were the most durable iPhones to date. After a battery of drop, shake and dunk tests, the phones scored a 4 and 5, respectively, out of 10 on the "breakability" spectrum. That's a better score than the Samsung Galaxy S5, which earned a 6, or the HTC One M8, which got a 6.5.

SquareTrade has not run any tests to see how susceptible these phones are to bending because the insurance company hasn't seen a phone this thin before, a spokeswoman said. She added that the company plans to run a bending test on the iPhone 6 Plus soon. (Other manufacturers, such as Sony and BlackBerry, have faced similar complaints about some of their phones.)

Over at iFixit, a Web site that tears down gadgets and scores them based on how easy they are to repair, engineers also noted that the new iPhones have improved durability. For example, the iPhone 6 Plus has rubber gaskets around the volume buttons to increase water and dust resistance, though that still doesn't mean you should be dunking your iPhone in water.

But iFixit chief executive Kyle Wiens said that he's not surprised to hear reports of bent phones; he's heard them before. "The iPhone 5S and iPads suffer from the same issue — we see bent phones all the time," he said. "The 6 is thinner, so it may be more susceptible to bending. I don't think it's a flimsier material — it's just less material overall."

To keep something so thin from bending, he said, you'd have to use a material such as titanium, which is impractically expensive and carries environmental concerns. Designers may be better off focusing on more durable phone designs, Wiens said, rather than on the current obsession with thinner, lighter devices. And if people want a phone that slim, he said, they should think about how to safely store it.

It's not clear how Apple's warranty would cover an issue like this. The warranty that comes with all iPhones covers "defects in materials and workmanship when used normally," so if the reports that the phones are warping just from being in a seated person's pocket are true, that might qualify as a defect.

Apple hasn't said anything to officially address these complaints. So there's no clear picture of how many people are having this problem, or if it's a launch hiccup on par with the iPhone 4's "Antennagate," which prompted Apple to give out free rubber bumpers to all those phone buyers.

Regardless of what Apple may or may not do on the issue, this underscores what iPhone 6 Plus reviewers have been saying all along: Get a case for this phone.