Bottom line: For Apple, it doesn't seem to be a matter of "if" they will build a foldable, but "when." We've heard rumors on the matter dating back to at least 2017 although nothing has publicly materialized yet. And really, it's probably wise to sit back and let others go first so they can see what does and doesn't work in the real world.

Apple is expected to launch a foldable iPhone featuring an 8-inch QHD+ flexible OLED display in 2023 according to respected industry analyst Ming-Chi Kuo.

In a recent note to investors seen by MacRumors, Kuo said he came to that conclusion based on his latest industry survey. SDC will serve as the exclusive display supplier "and Samsung Foundry as the exclusive DDI foundry provider," Kuo added.

The analyst also expects Apple to adopt TPK's silver nanowire touch solution due to its advantages over SDC's Y-Octa tech.

Artist interpretation of what a foldable iPhone might look like

Kuo believes that, based on Apple's requested capacity, the company is aiming to ship 15 million to 20 million foldable iPhones in 2023. He further predicts foldables will become a must-have and help create the next big upgrade super cycle.

As Kuo correctly identifies, the current crop of foldable smartphones don't really do a great job of blurring the lines between smartphone and tablet. They're also a bit rough around the edges as manufacturers are still working through design and durability issues. Eventually, however, Kuo sees foldables as devices that more seamlessly blend elements of smartphones, tablets and laptops into a single device.