Android 4.0, also known as Ice Cream Sandwich, marks the start of a new era for Google's mobile platform. Nearly every facet of the OS has been made over, and the very core of the Android user experience has been completely reimagined.

The more you use Ice Cream Sandwich, the more you realize just how radical a change it represents.The first thing you notice when you start using Ice Cream Sandwich is that Android suddenly seems a lot more friendly. At a glance, Ice Cream Sandwich seems similar to the Android of years past. You have five home screen panels that hold any combination of app shortcuts, folders and live functioning widgets.Tapping the microphone at right end of the box, meanwhile, brings up Google's Voice Actions utility, which allows you to conduct a Web search, place a phone call, send a text or email, or get driving directions by speaking into your device.

Ice Cream Sandwich introduces a newly designed app drawer that puts all of your installed applications and widgets in a single centralized place.

Ice Cream Sandwich gets a brand new notification bar that houses icons and information about incoming messages and alerts. It's essentially a prettier and more powerful version.

Google has really gone a long way in improving the system keyboard in Ice Cream Sandwich. It is better at predicting and correcting text, which means you can type quickly and/or sloppily and it'll almost always figure out what you're trying to say.

When your phone is locked and you receive a call, the lock screen features a new text-and-reject feature that simultaneously declines the call and sends a message to the person explaining why you can't talk. 

One of the high points is the newly implemented support for zero shutter lag. That means you can snap one photo after another in rapid succession without ever having to stop or wait.

 It also introduces an intriguing new option: facial recognition for phone unlocking.

Android has always been a powerful platform. With Ice Cream Sandwich, its power reaches new heights -- and its polish makes the power more palatable than ever.