Originally Posted by PetiePal
Actually the sensor is the most important factor in any camera. Go read up on Gizmodo/Engadget regarding this. 5MP is more than enough for a camera on a smartphone. If you really want "12MP" get a regular camera, these devices are never meant to be that high rez.
The key to understanding this matter is the pixel density on sensor, number of pixels per unit area (/mm^2 or /inches). Lower the pixel density, it's better because each pixel size is bigger and can receive more light. DSLRs have much larger sensor than P&S cams and phones. So it has lower pixel density compared to P&S with same MP, leading to low noise clean images. On top of that, it has high quality large aperture lens that can let plenty enough light to sensor at fast shutter speed.
The limiting factor in phone camera is small sensor size like 1/7~1/8". Cramming 8MP into that size sensor is probably equivalent to 20MP or more in P&S camera sensor. No one in right mind in photography would want that. Of course 1MP or lower pixels will result in poor sharpness, low resolution. But bumping it way above sweet spot in pixel density will gain nothing in image quality and actually would hurt it.