Android Round Launcher Icon

So the Google Pixel now allows you to use a round icon as your launcher icon. I've seen incredibly few apps implement this, even most Google apps have yet to update. That got me wondering how to achieve this new amazing (not at all copied from Apple) roundness?

The answer is this new tag in your manifest application:

<application
    android:icon="@mipmap/ic_launcher"
    android:roundIcon="@mipmap/ic_round_launcher"

Android is clever enough to apply this only to phones that support it and lets you
provide a normal boring square icon for old phones.

You are given this error in the IDE which is annoying:

  
    Resources referenced from the manifest cannot vary by configuration 
    (except for version qualifiers, e.g. -v21.) Found variation 
    in hdpi, mdpi, xhdpi, xxhdpi, xxxhdpi
  
It can safely be ignored or suppressed though.