Can anyone tell me how to take a scan of a trail map (Like this http://www.njhiking.com/nj-hiking-ma...-trail-map.pdf ) so as to be able to use it with the location/GPS feature on a iPhone?

I can trace it on a piece of clear plastic and tape it to my iPhone to overlay the Maps program, but there must be a better way which I've been unable to find.

Thanks