It looks like the Huawei P20 Pro is no longer the only phone with a triple camera. Rumor has it that the upcoming LG V40 ThinQ will have the same number of cameras. And as with dual cameras, LG shows that there are several ways to arrange them.
With the Huawei P20 Pro, Huawei has extended its existing dual-camera setup with a third sensor. Most Huawei and Honor devices used an RGB and a monochrome array, so it only made sense to use that as the basis of the triple camera and improve it with a telephoto lens. Take advantage of the details of the 40 MP RGB lens and the sharpness of the 20 MP monochrome lens, and combine it with the 3x optical zoom of the telephoto lens.
For LG they took similar steps. For years, LG's flagships have been known to use a main lens with a super wide-angle lens so their customers can incorporate more objects into each photo. The V40 ThinQ shows rumors that the super wide-angle (or "ultra-wide") will return with a "super telephoto lens". It looks as if the telephoto lens offers a 3x optical zoom and offers the same lossless zoom function as the P20 Pro.