title: How to draw rullar in iphone sdk?
body: <p>Hi I want to make rullar in iphone.
  Que: How to draw lines through <code>UILabel</code> in <code>scrollView</code> 1 inch. or 1 cm. apart from each other.
  I know there are 163 pixels per inch(ppi). in 480-by-320-pixel.
  But I am not sure about all version of iPhone .</p>
  
  <p>Does the size of pixels are same for all its model??? </p>