One of the 4.0 features is Disabling Apps
Android Ice Cream Sandwich has a new feature that lets users disable practically any application they may want to, including those pesky carrier pre-installed apps that can strain device resources and drain battery even if you choose not to use them
I dont see this in the emulator and neither do i see any API for the same.
Can anyone help me here?
It is enabled in the emulator, though it's likely not where you'd expect to find it :)
Choose an app that's "preinstalled" (for this example, the browser works).
Drag it to the top of the screen where it says "App Info".
Release.
In the resulting screen, you'll be presented with two buttons near the top. "Force Stop" and "Disable".
To answer the second part, currently there's no API for this feature.
EDIT: To re-enable an application, go to Settings > Apps > "All" tab, scroll to the bottom. Disabled apps will be labelled as such. Just select the app, and click "Enable" where the disable button was before.