According to a report from Korea, Apple ordered an extra 60 million flexible OLED panels from Samsung Display for the next-generation iPhone, in a deal worth 5 trillion Korean Won, or about $4.3 billion.
The report says that this deal is an addition to Apple's original OLED order in late 2016. That 2016 deal, for 100 million OLEDs, was estimated at $4.3 billion as well, so it may be that this is actually the same display order that is just now being reported again.
All previous reports suggested that Apple will only use OLED displays in a high-end version of the iPhone - but 160 million displays is about 80% of Apple's entire yearly sales - which seems a bit high for the first generation OLED iPhone.
This same new report also claims that Samsung Electronics has set a sales goal of 60 million units for its upcoming Galaxy S8. The Galaxy S7 sold 48 million units in total, while the S6 and S5 sold 45 million units each.