Layers to separate different parts of the doodle. Also all sort of
brushes and filters and no mess or bulky bags to carry with me every time i want to color any doodle.

It allows you save multiple versions of the image in case you want to make changes to it : )

Check this You tube video by Kitty Luna on how to color and draw 
roll over the face above
Photoshop works really well, and it offers unlimited shades and hues not to mention  other features such as:
Tip # 1
roll over the flower