How to manage and scale graphic assets across different screen resolutions in LibGDx, as implemented in Orble https://play.google.com/store/apps/details?id=com.chandruscm.orble.android

ManagingAssetsLibGDx

/*
3 set of assets are used for targeting 480p, 720p and 1080p+ resolutions
These are packed in TextureAtlases placed in folders SD/, MD/, LD/ respectively inside res/
Each containing the TextureAtlas with the name gameScreen.pack
*/

public static float dpiScale;
public static String dpiPixel;

//Check if the dpiScale has been calculated, if not find it and save it to preference(only for the first run)
if(preferences.contains("dpiScale") && preferences.contains("dpiPixel"))
{
	dpiScale = preferences.getFloat("dpiScale");
	dpiPixel = preferences.getString("dpiPixel");
}
else
	setDpi();

//Initial choice is based on the screenWidth
private void setDpi()
{
	int screenWidth = Gdx.graphics.getWidth();
	int screenHeight = Gdx.graphics.getHeight();

	//Taking minimum gives the most appropriate scaling factor.
   if(screenWidth < 720)
	{
		dpiScale = Math.min(screenWidth/480f, screenHeight/854f);
		dpiPixel = "SD";
	}
	else if(screenWidth < 1080)
	{
		dpiScale = Math.min(screenWidth/720f, screenHeight/1280f);
		dpiPixel = "MD";
	}
	else
	{
		dpiScale = Math.min(screenWidth/1080f, screenHeight/1920f);
		dpiPixel = "LD";
	}
	preferences.putFloat("dpiScale", dpiScale);
	preferences.putString("dpiPixel", dpiPixel);
	preferences.flush();
}

//Load the correct TextureAtlas in AssetManager
getAssetManager().load("res/" + dpiPixel + "/gameScreen.pack", TextureAtlas.class);

//Scaling the sprites
private Sprite setScaledSprite(TextureRegion textureRegion)
{
	Sprite sprite = new Sprite(textureRegion);
	sprite.setSize(sprite.getWidth() * dpiScale, sprite.getHeight() * dpiScale);
	sprite.setOriginCenter();
	return  sprite;
}