This app make sketch from camera or photo library on your iPad. After taking a picture, user can color on it.
This app support 5 different pen width, and more than 12 colors.

Kids take a picture of their favorite toys and dolls, and color on it by their hand.

Tip: If light source is behind the object, sketch is not good because of shadow. But unfortunately, iPad don't have flash light, so you can get more clearer sketch by using phone's flash light. :) Thanks.