Are you cropping and zooming or cropping and enlarging the picture? That's going to generally reduce the quality of any picture. There just isn't enough information on the camera to keep the details of the photo at a greater zoom or enlargement, especially on a camera phone. I've never used an iphone much, but the pictures generally come out nice and clear from what I've seen. Don't crop, just get the snake in the photo, use macro mode if you're too close (I'm not sure if iphone has this or how to direct you to it), then just post the photo as is. Also, try not to use the zoom feature on the phone if you can, shoot the photo at the lowest zoom (i.e. no zoom).