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You need to override here, won't work if just add it to your viewport.
So create a folder "override" in your app folder and in it a folder "viewport".
Then put the above code in an Android.js file and adjust the app namespace:
Then add 'myApp.override.viewport.Android' in the requires array in your app.js file.
You can add a alert message in the doFix method to make sure it's called on your Android device.