CoronaCards lets you take advantage of the power and ease-of-use of Corona, in any native app. You include it in your project like any other SDK and can display CoronaCards in any configuration (i.e., full screen, partial screen or transparent overlay).
In other words, with Corona SDK/Enterprise, the full app is built with Corona. With CoronaCards, you have an app built natively or in another framework and then bring Corona into the mix.
Since you are using the same underlying platform, you can take advantage of almost all of Corona's 1000+ APIs
. These include displaying OpenGL-accelerated graphics, audio, physics, animations and much, much more.