Reports coming from Korea, picked up MacRumors, indicate that the 2020 iPhone will likely have thinner displays. They could also be more power-efficient too.
This mirrors a recent report from Korean website ETNews, which claimed that so-called iPhone 12 Pro models will adopt a technology that allows touchscreen circuitry to be directly patterned on the OLED panel without the need for a separate layer, resulting in a thinner display and lower production costs. ETNews said a lower-cost 6.1-inch model, presumably the iPhone 12, will stick with a traditional film-based display. It is unclear if thinner displays would translate to thinner iPhones as a whole this year.