It is believed that the dual cameras in smartphones is not limited
On the website CNET published an article on the topic that dual camera in smartphones is just the beginning of a trend, which will cause to appear on the market the device with three, four and greater number of cameras.
You should start at least with the fact that the market already have the Lenovo 2 Pro Phab with the main camera, which includes three modules. The authors recall presented in 2015 the first «multi-aperture computational camera» Light L16, which is comparable with smartphones the case. It has 16 cameras that allow you to implement the function of a five-fold optical zoom and get high-quality photos with resolutions up to 52 mn, particularly in low light conditions.
Two cameras in the iPhone 7 Plus and Xiaomi Mi 6, allow to realize a fixed a two-fold approach. If you install to the smartphone three or more modules with different focal lengths, it is possible to realize a higher quality zoom function and capture more light to reduce the noise and improve picture quality.
I wonder who was the first smartphone manufacturers will start to move in this direction.