I'm a bit confused as to what resolutions I should be saving my images in for the different drawable folders. Is there a general formula for it? For example,if I want an image to take up 10% of the height and the full width of the screen, roughly how would I calculate what different resolutions I should save the image in?
This is android's guidelines for icons. Obviously not all drawables are icons, but maybe this helps you get started.
From here: http://developer.android.com/guide/practices/screens_support.html