Corona - How do I place different device resolutions while maintaining quality for high resolution devices?

How can I place lower resolutions from Corona, but are primarily aimed at high-resolution devices?

I know that you can set the width and height of the content through Corona and scale the content, but it seems to scale up (the method is described in detail here http://blog.anscamobile.com/2011/01/use-dynamic-layouts- in-universal-builds-with-corona-sdk / ).

I am creating an application for the iPad, but have not configured any resolution - my application looks great on the iPad 1/2 and on the iPhone 4, but not on the original iPhone.