DxO review.
But we don't really need a review. Image sensor size is determinant of IQ. You can't make up for a small light collection surface with image processing, not in low light conditions.
iPhone 7: 1/3" sensor, f/1.8 (1/3.6" sensor for zoom lens)
Samsung Galaxy S7: 1/2.5" sensor, f/1.7
I think the Google Pixel's sensor may even be larger than the Galaxy S7's.
Part of the problem is Apple's obsession with Thin. It limits the camera module choices. Personally I'd prefer a thicker phone with a larger battery and better camera.