Drawing a line is very easy indeed, the "problem" is that drawing a line is an ill defined "request", you need to decide what color you want your line, what width etc. Anyhow, in your view's drawRect method (assuming you're subclassing a view, that is you have a class that inherits UIView and you are making an instance of this class viewable): in drawRect: CGContextRef ctx = UIGraphicsGetCurrent..
