Aspect Ratio Problem?

hello everyone ,
i need to know what's the best aspect ratio that work with almost all mobiles.
thanks

what's the best aspect ratio

hello everyone ,
i need to know what's the best aspect ration or screen resolution for design a game on android and to be fit with a wide range of mobiles' screens. i don't know more about aspect ratio and it's diff a little from one mobile to another .
thanks.

Camera Sensors Native Aspect Ratio?

Has anyone heard the native aspect ratio for the camera sensors? On the Nexus 6 it was 16:9 on the front but 4:3 on the back. I can handle the front being 16:9, but if the back isn't 4:3 I will be seriously annoyed. I was hoping for a jump to 16mp so this would further hurt my pictures because I would be forced to crop down to 4:3.

If you know, please link to a source.