title: get versionName from within a webview
body: <p>I have a webview and on one of the pages I have an "about the app" page which shows the current version app version. However I fear if I have to change the app at some point in the future the version will become misaligned as I have to update it separately in the php webpage.</p>
  
  <p>Is there some code I could use to get the android:versionName as a variable and output the variable (preferably php but I'm open to using other methods).</p>
  
  <p>I would like it if i could use a simple variable like <code>if($_SERVER['HTTP_X_REQUESTED_WITH'] == "com.klingondragon.fakeappname") {</code> which I use to check if a browser is being used or if it's coming from the app.</p>