At the moment, Apple’s lineup of iPhones consists of te iPhone XS, XS Max, and the iPhone XR, the former two being OLED models while the latter uses LCD. There have been talks that Apple could eventually make a full transition to OLED screens in the future, and according to analyst Samik Chatterjee, that could happen in 2020.
According to Chatterjee, he claims that in 2020, Apple is expected to launch a trio of high-end iPhones, all of which will be sporting OLED displays along with support for 5G. The report goes on to claim that the display sizes offered will be 5.4-inches, 6.1-inches, and 6.7-inches. For those who are wondering if this means that Apple could introduce OLED to its lower-end iPhone, you might be disappointed.
This is because Chatterjee claims that the use of OLEDs will be for the higher-end iPhone models, but he also notes that Apple will continue to make a budget version, which presumably will keep using LCD as it is cheaper to produce. In addition to OLED, the analyst claims that Apple will introduce support for 5G in its 2020 iPhones, along with a rear-facing ToF 3D sensor for the camera that will be used for both augmented and virtual reality applications.
Safe to say that you should probably take this with a grain of salt for now, but these are claims that we have heard before so if anything, the rumors are consistent.