The Android Design Guide states that the launch icon should be 48dp across, with a 1dp padding inside it on each side, which means the actual icon is 46dp (with a square sign). https://www.google.com/design/spec/style/icons.html#icons-product-icons
But when I use the launch icon creation tool in Android Studio (from the image), it creates an icon with a lot more additions than this (it does not come from the original image). For example, my mipmap-xxxhdpi object is 192x192px, as expected, but excluding the Android Studio add-on, the icon added is only 160x164px, which is equivalent to 40dp, not 48dp.
It seems to me that Android Studio is not able to accept the Android design guidelines regarding startup icons, and also add significantly more add-ons than necessary, but I will post here if I miss something.
Refresh, added an example showing an extended add-on.
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