Android.

Android is the great platform. Following are few things I think that makes the platform powerful.

1) Integration.
2) Customization.
3) Simplicity.

Integration:

Customization:
Android supports Shortcuts and Widgets. For power users (Those who customize the phone for their need), These two feature makes their life much easier.

Using shortcut, user can easily do simple action from a single click. In UCA application two types of shortcuts are included, Shortcut for Changing status and Shortcut for viewing/Calling Contact. Some UCA users works with two status, "In the office" and "Out of office" For them having two icons on the home screen to change the status is more handy than to launch the app and click the status and select the new status.

Shortcuts are for static actions, widgets on the other hand is for customizing applications the realtime data. Widget gives an impression a small portion of the home screen is controlled by the application itself. In UCA there are two widgets provided small and big one. On content wise both are similar, both publishes the call routing status, last few missed calls and last few voice mail messages. And clicking on each portion would take to the appropriate view.

In the Honeycomb OS, Google had introduced two more type of widgets, Stacked view and Grid view. Both looks nice on Xoom.