Google suggests to create for each image 4 different versions – one for each density (ldpi, mdpi, hdpi, xhdpi). Sometimes you might even want to create others, based on the screen size (small, normal, large, xlarge).
This causes a weird situation where most of the app’s images will never be used by the app, right?
How come Google doesn’t create multiple APKs on their website, to target the best APK to the end user’s device, so that 100% of the resources will be targeted on the device’s specs? Or there is already such a thing?
Yes there is a support for multiple APK. Please refer here.
To address your need precisly you can certain filters in your manifest file i.e.
<supports-screens> or <compatible-screens>