Both Samsung Galaxy Camera 3G and Nikon L31 have 16.0 MP resolution sensors but Samsung Galaxy Camera 3G's sensor is 1/2.3-inch (6.17 x 4.55 mm ) and Nikon L31's sensor is 1/2.3' (6.17 x 4.55 mm ).
Since Nikon L31's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Samsung Galaxy Camera 3G.
Below you can see the Galaxy Camera 3G and L31 sensor size comparison.
Samsung Galaxy Camera 3G and Nikon L31 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture.