Why is the Motorola Xoom (Dual Core) slower than the Samsung Galaxy S (Single Core)?

Why is the Motorola Xoom (Dual Core) framerate (an average of 20 fps) lower than the Samsung Galaxy S (Single Core) framerate (an average of 31 fps) in my Unity3D-Application? It has to do with the resolution and the size of the display? Is there a setting in Unity, where can I fix this?

Use the built in profiler, described here:

This should help you work out if you are CPU bound or GPU bound. If you are GPU bound, then yes, it is probably because of the number of pixels that the devices have to render. There’s no “setting” that you can tweak. Instead either draw fewer pixels or change the shaders that you use to make them less expensive.

Here are also some information:

http://forum.unity3d.com/threads/88137-Android-Tegra-2-performances-slower-than-iPad