This type of LCD monitor will be cheaper and probably will have less supply problems than OLED being used by iPhone X, two factors that contribute to the price of iPhone X so high.
One of the 2018 iPhone phones has screens up to 6 inches wide
Galaxy Note 8 with a 6.3 inch screen may be similar to what Apple intended for its successor iPhone 8 Plus
According to the Korea Herald, Apple ordered Japan Display for a 6-inch LCD screen. Because it is LCD panel, not OLED, this will be the successor of iPhone 8 Plus, not iPhone X.
If the iPhone 2-18 has almost no bezel, this means the end of the iPhone 6 era design
This is just a guess based on the rumor that Apple will use the Full Active LCD screen, one of which is said to be larger than the 5.5-inch screen of the iPhone 8 Plus. Meanwhile, the iPhone 2018 looks very different, no big bezel on the iPhone 8, which is the design from the iPhone 6 launched in 2014.
IPhone X's successor in 2018 will also be bigger
According to ET News, Apple ordered Samsung Display, the manufacturer of OLED displays of iPhone X, for OLED screens 5.28, 5.85 and 6.46 inches, but the smallest size was canceled.
Both iPhone X will also be able to have a bigger screen
Rumor has it that Apple will bring more 6.46-inch screens to iPhone X's successor next year. The coming iPhone X this month only has a 5.8-inch OLED display.