Something I’ve recently found out: Most of my mobile camera pictures suck. It’s mostly due to my lack of attention to this, and particularly due to my lack of understanding of the Android Camera. Some cameras do a fantastic job with guess about the focus of the picture. However, I found that the circle in the middle of the preview window is what is identified as the focus.
For those who don’t know, the focus identifies the subject of the picture. With many of the cameras that attempt to optimize the light balance, the focus is used to make the guess.
So in short, to take a better picture, move the focus circle on the camera to where your main subject is and then take the picture. If you want an even better picture, attempt to play with the white balance (which is the little sun light meter surrounding the focus circle).