How can dual cameras improve the effect of taking photos on mobile phones?

Dual-camera mobile phone was the most popular mobile phone type last year. Various manufacturers are committed to dual-camera mobile phones. The principle is to use two lenses to record the depth of field information, and add an algorithm to identify the edge of the object to blur it, so as to realize the background blur and portrait effect. What is better than SLR, and what the cosmic background is blurred are all gimmicks. Dual-camera phones have limited effect on improving the level of photography. Give a few examples.

Leica Huawei cooperates with two lenses. Leica mainly provides the so-called German color presentation, and the blurring algorithm should be provided by Huawei itself. Double camera is not a leap in camera level, but a gimmick.

With the release of Google pixel2, Google's own son with only one rear camera was rated as the best camera phone ever by foreign media DXO professional photography evaluation agency. Even if it is controversial, it shows that the so-called background blur and portrait mode do not necessarily depend on two cameras, and the problems that the algorithm can solve never need hardware. This is Google's solution, and it also makes many dual-camera flagship phones feel ashamed.