Bloomberg: only one iPhone 8 model with OLED display planned, as Samsung can't make enough flexible screens
33

Apple has already figured in there will be high demand for the OLED model and they’ve also figured out there will be constraints to these panels.
Why not go all in, and release all planned iPhones for next year with OLED displays then, if Apple has already put research in the technology and has deemed it mature enough to go into a groundbreaking design overhaul? Well, Bloomberg today reports that there simply aren't enough OLED screen panels to go around, and yields won't sufficiently improve to carry Apple's level of demand until some time in 2018.Bear in mind that we aren't talking about the regular Super AMOLED screens that Samsung is placing in phones like, say, the Galaxy A7. As per Bloomberg's sources, Apple intends to use flexible OLED displays, like the one of the S7 edge, so that the iPhone 8 has a "new look that extends glass from the display to the device’s back and edges." This type of OLED screens use plastic, instead of glass substrates, so that they can be bent, and there simply isn't enough yield of those just yet, at least not with Apple's stringent quality requirement.
Oh, well, one disruptive model will have to do for next year. On the plus side, Bloomberg's sources reconfirm that the "premium" iPhone 8 with curved OLED panel will be mostly screen at the front, and solve the home button conundrum by embedding it in the display itself. Good times ahead.
source: Bloomberg
Things that are NOT allowed: