Update readme

README.md

@@ -165,7 +165,8 @@ var options = {
   files: ['', ''], // an array of filenames either locally or remotely
   url: 'https://www.website.com/foo/#bar?a=b',
   chooserTitle: 'Pick an app', // Android only, you can override the default share sheet title
-  appPackageName: 'com.apple.social.facebook' // Android only, you can provide id of the App you want to share with
+  appPackageName: 'com.apple.social.facebook', // Android only, you can provide id of the App you want to share with
+  iPadCoordinates: '0,0,0,0' //IOS only iPadCoordinates for where the popover should be point.  Format with x,y,width,height
 };
 
 var onSuccess = function(result) {