I am developing an application for Android and I'm using the API level 8. However I would like this app would use the theme of ICS when running on Froyo and Gingerbread because the theme of the ICS is much more beautiful. I wish that at least the color scheme and shape of the buttons were equal. Is there any way to do this?
The first thing you might want to look at is ActionbarSherlock as it adds a lot of consistency to your pre-ics code, even though this is not directly related to the theme.
Then take a look at the HoloEverywhere project on GitHub for using the Holo theme on apps designed for pre-ics devices.