How many iPhones have you read e-books on? According to Apple executive Phil Schiller, that’s asking the wrong question—because you ought to ask either “how many iPhone” with no “s,” or “how many iPhone devices.”
— Philip Schiller (@pschiller) April 28, 2016
Apple product names apparently work for both the singular and the plural form, if you don’t want to add the extra word. So the plural of the Macintosh would either be “3 Macintosh computers,” or just “3 Macintosh,” Schiller said.
“Words can be both singular and plural,” he explained, even if seems counterintuitve, “such as deer and clothes.” One deer, ten deer. One iPhone, ten iPhone (or ten iPhone phones).
The whole thing is more than a little silly—especially given that Apple has pluralized its own product names plenty of times itself. But then, Schiller didn’t say you can’t ever pluralize them, just that you don’t have to.
It may also have something to do with not wanting to genericize Apple’s trademarks, as happened with Kleenex or, more recently, Google. In any event, it’s certainly not the way most people refer to the devices. But perhaps it should be.