Update adding-buttons-to-the-navigator.md

docs/adding-buttons-to-the-navigator.md

   rightButtons: [{ // buttons for the right side of the nav bar (optional)
     title: 'Edit', // if you want a textual button
     icon: require('../../img/navicon_edit.png'), // if you want an image button
-    component: 'example.CustomButton', // if you want a custom button (iOS only)
+    component: 'example.CustomButton', // if you want a custom button
+    passProps: {}, // Object that will be passed as props to custom components (optional)
     id: 'compose', // id of the button which will pass to your press event handler. See the section bellow for Android specific button ids
     testID: 'e2e_is_awesome', // if you have e2e tests, use this to find your button
     disabled: true, // optional, used to disable the button (appears faded and doesn't interact)
     disableIconTint: true, // optional, by default the image colors are overridden and tinted to navBarButtonColor, set to true to keep the original image colors
     buttonColor: 'blue', // Set color for the button (can also be used in setButtons function to set different button style programatically)
     buttonFontSize: 14, // Set font size for the button (can also be used in setButtons function to set different button style programatically)
-    buttonFontWeight: '600', // Set font weight for the button (can also be used in setButtons function to set different button style programatically)
-    passProps: {}, // Object that will be passed as props to custom components (iOS only, optional)
+    buttonFontWeight: '600' // Set font weight for the button (can also be used in setButtons function to set different button style programatically)
   }],
   leftButtons: [] // buttons for the left side of the nav bar (optional)
 }
 * accept
 * sideMenu
 
-#### Custom Navigation Buttons - iOS only
+#### Custom Navigation Buttons
 
-react-native-navigation uses `UIBarButtonItem` to display all items in the navigation bar. Instead of using images or text for normal `UIBarButtonItem`s, you can supply a custom component to be displayed within a custom view of a `UIBarButtonItem`, using the `component` property when specifying a navigation button.
+On iOS, react-native-navigation uses `UIBarButtonItem` to display all items in the navigation bar. Instead of using images or text for normal `UIBarButtonItem`s, you can supply a custom component to be displayed within a custom view of a `UIBarButtonItem`, using the `component` property when specifying a navigation button.
 
 Custom components must first be registered, just as screens are registered, using [`Navigation.registerComponent`](#/top-level-api?id=registercomponentscreenid-generator-store-undefined-provider-undefined).