Over at Vice/Motherboard is an article on the expected lifetime of apple phones [vice.com], based on the proceedings in a class action lawsuit over problems with iPhone 6 and iPhone 6 Plus devices.
When it released its iPhone 7 Environmental Report [apple.com] a year ago, Apple wrote that it "conservatively assumes a three-year period for power use by first owners," which is "based on historical customer use data for similar products."
Greg Joswiak, Apple's VP of iOS, iPad, and iPhone Marketing, told Buzzfeed last month [buzzfeed.com] that iPhones are "the highest quality and most durable devices. We do this because it's better for the customer, for the iPhone, and for the planet."
But in court, Apple argues that it is only responsible for ensuring the iPhone lasts one year, the default warranty you get when you buy an iPhone.
This case in question is related to problems with the touch screen, as the soldering connections to the controller IC fail. However this failure only occurs after months of normal usage.
In that court case, currently being litigated in California, the plaintiffs attempted to argue that "consumers reasonably expect that smartphones will remain operable for at least two years when not subject to abuse or neglect because the overwhelming majority of smartphone users are required to sign service contracts with cellular carriers for two year periods."
Apple's motion to dismiss in that case noted that the plaintiffs' phones broke more than a year after they were purchased, which is after the warranty expired. If your phone breaks after the warranty is up, well, you're out of luck, Apple argues.
Arturo González, the lawyer representing Apple in the case, wrote in the motion [...] that it is "not appropriate for courts to rewrite the express terms of a warranty simply because of a consumer's unilateral expectations about a product."
More background on the case from last October in Fortune [fortune.com]