When you’re working with graphic assets in Android, it’s nearly impossible to avoid importing bitmap files in your project. And that’s ok because for a complicated design (with many shadows and textures for instance) it’s the right solution. Trying to make these graphics work with multiple screens though will eventually get ugly because you’ll have to use 3 or 4 versions for each bitmap. It makes sense then to use any non-bitmap solution where you can. Android’s layer-list is one of these powerful solutions.