I love ice creams and i love sandwiches. But now, i love ice cream sandwiches. Its finally out :-

http://developer.android.com/sdk/android-4.0-highlights.html#DeveloperAp

A brief summary about what it offers for developers :-

1) A fantastic UI framework that works on mobile too. If your jaws fell open when you saw honeycomb and you have been sweating to make your mobile app look the same, then despair no more. This release comes with a unified UI framework that allows you to create the same cool UI for your phone too.

2) Then there are the new set of API's for social , calendar and voicemail.

3) We can now use NFC

4) A new widget on action bar to share stuff with others

5) a new low level media streaming API based on OpenMAX AL

6) cool camera features to do some really cool things with the camera while taking pictures or video.

7) images or video transformation API's that help you to manipulate images or video and apply filters or effects on them

8) audio remote control API for media apps. Now you can control your media application from outside your application.

9) stylus input  - now handwriting recognition and drawing can be fine tuned

10) a new layout - GridLayout. Now that is an another one. More details on their site.

A few ( a lot ) of API's have been modified or changed. Now this is something we have to be careful about. More details here - http://developer.android.com/sdk/api_diff/14/changes.html

Google Nexus is the only phone running android 4 today - http://www.google.com/nexus/