https://www.cnet.com/news/iphones-may-get-three-cameras-and-apple-surprises-valve/

Dual cameras, schmual cameras -- how about three? A new analyst report speculates that the 2019 iPhone will have one telephoto lens and two more to create a depth map for AR. 

Those three iPhones rumored for 2019 are also suspected to all use OLED screens, just like the iPhone X. This screen technology is known for producing rich color with high contrast and deep blacks.