How to draw a realistic eye

I used the app sketchbook pro on my Ipad2, to do this , this took time 10-18 minutes, I drew this in a black and white version thanks c:

First draw a normal eye shape and the pupil In the middle as demonstrated

Then start from the bottom drawing eyelashes on different sizes from left to right, once done where the eyelashes attack draw over with black brush ( or ink pen of using paper)

Then you start with the top, do the same except don't go over with black brush yet

Now you add it then draw an eye shape inside the eye around the pupils at the bottom you draw little tiny eyelashes

Then inside instead of using ink you shade the eye like a circle in the middle and outside it's surrounded , I faded this using a fade tool but if using paper use pencil to shade it or an oil tip pen.