BGR claims Apple will give in to this pressure and start using OLEDs in 2018, which (assuming Apple continues to follow current traditions) would be the year of the iPhone 8 and iPhone 8 Plus, the 7s generation having launched in 2017.
OLED screens are more desirable than LCD in a number of ways: they produce sharper, more brightly coloured images, and are more power-efficient. (The Apple Watch uses an OLED screen.) But they cost more to manufacture, which explains Apple's reluctance to deploy them in iPhones thus far.
Source: Macworld UK
Sign up for Computerworld eNewsletters.