A coloring book (British English: colouring-in book, colouring book, or colouring page) is a type of book containing line art to which people are intended to add color using crayons, colored pencils, marker pens, paint or other artistic media. Traditional coloring books and coloring pages are printed on paper or card. Some coloring books have perforated edges so their pages can be removed from the books and used as individual sheets. Others may include a story line and so are intended to be left intact. Today, many children’s coloring books feature popular cartoon characters. They are often used as promotional materials for animated motion pictures. Coloring books may also incorporate other activities such as connect the dots, mazes and other puzzles. Some also incorporate the use of stickers.
Coloring book for iphone, Thus, it can be concluded that coloring books meet the kids' need of expressing themselves creatively and no one has to spend money on getting the pictures for coloring.