News out of Korea today is that Apple and Samsung Display have signed a contract for the supply of as many as 60,000 flexible OLED panels per month, according to ET News. This puts Samsung in the leading position to supply OLED screens for Apple's anticipated future switch in iPhone display tech, with LG Display, Japan Display, and Foxconn also said to be in the running to serve as Apple's secondary supplier.
By this point, Apple's development of an OLED iPhone display is almost an open secret, with LG Display and Japan Display both making significant investments into expanding their production capacity in anticipation of competing for Apple's business. Notably, the two suppliers are expecting their new facilities to come online in 2018, which is the year most rumors have pointed to Apple switching from its established practice of using LCD panels to the self-illuminating OLED alternative.
2018, 2017, or even 2016?
A recent report from Nikkei accelerates the timeline from 2018 to 2017, suggesting that Apple is ahead of schedule and the first new iPhone with OLED would be the 7S, if Apple maintains its current nomenclature. The ET News article agrees with the Nikkei that Samsung and LG are indeed in the lead to secure Apple's orders, though it talks about the "next iPhone," which would ostensibly be this year's upcoming iPhone 7. That wouldn't be completely out of the question with Samsung beginning supply now, but seems unlikely given the absence of any other corroborating reports.
While the two Korean display makers are evidently favored by Apple — and undoubtedly most experienced with producing OLED panels — there is also the dark horse competition of Foxconn to be considered. It's a company that Apple relies on extensively, and should it complete its protracted takeover of Sharp, it would have a great deal of display-making competency of its own. That being said, with Apple's apparently faster roadmap, Foxconn might have to look to compete more strongly in later generations of the iPhone.
Check out LG's flexible OLED screen from CES 2016