https://phys.org/news/2019-01-three-camera-iphone.html

According to The Wall Street Journal, Apple will once again introduce three new phones this fall, with three rear cameras for its highest-end model. The other two models, including a possible iPhone XR successor with an LCD display, will have two cameras on the back.

In 2018, the pricier iPhone XS and XS Max each had two rear cameras to enable better zooming and a more robust "portrait" mode. The iPhone XR, which starts at $749 ($250 less than the $999 iPhone XS), had only one rear camera as well as a cheaper LCD display instead of using the XS line's higher-quality OLED technology.