Set icon for Android application

If you intend on your application being available on a large range of devices, you should place your application icon into the different res/drawable... folders provided. In each of these folders, you should include a 48dp sized icon:

• drawable-ldpi (120 dpi, Low density screen) - 36px x 36px
• drawable-mdpi (160 dpi, Medium density screen) - 48px x 48px
• drawable-hdpi (240 dpi, High density screen) - 72px x 72px
• drawable-xhdpi (320 dpi, Extra-high density screen) - 96px x 96px
• drawable-xxhdpi (480 dpi, Extra-extra-high density screen) - 144px x 144px
• drawable-xxxhdpi (640 dpi, Extra-extra-extra-high density screen) - 192px x 192px

You may then define the icon in your AndroidManifest.xml file as such:

<application android:icon="@drawable/icon_name" android:label="@string/app_name" >
.... 
</application> 

Add an application launcher icon with automatic sizing.

(Android studio)

Go to menu File* → New → Image Assets → select launcher icon → choose image file.

It will automatically re-size.

Done!