title: iOS UIWebView Javascript - insert data -receive callbacks?
body: <p>I have a webpage.  I have a javascript file that does a whole lot of stuff.  In the app I have an NSString with some crucial data that needs to be processed in the javascript file.  How do I get my string value into a certain place in my html so my javascript can read it?</p>
  
  <p>Also, the javascript will produce certain data when actions are performed (like pressing a button), how do I retrieve the data from the webview/javascript so it can be stored in the app?</p>