Neha,
Default leaves implementation doesn't handle hyperlinks, you must
supply that functionality withing your application. There is a good
article about how to get hyperlinks dictionary here
http://stackoverflow.com/questions/4080373/get-pdf-hyperlinks-on-ios-with-quartz
also you will need to create a handle for touch events on leaves view
to compare pressing point against link areas (don't forget to take
into account zoom level in comparison if you enable zoom handling when
page is zoomed in / out), after that you will need to create a way to
deal with the selected link (such as opening a browser or changing to
another view inside your app).
Hope this helps,
Cheers!