I have seen some mobile phone specifications that mention "12MP + 12MP Camera", such as these specs for a Samsung Note 8:
12MP + 12MP Camera
8MP Front Camera
6.3" Display
64 GB Memory
6 GB Ram
2.3 + 1.7 GHz Octa Core
Does "12MP + 12MP" mean that the camera has 24 megapixels in the camera, or just 12 megapixels?