Google just announced the latest upgrade to their mobile operating system Android 4.1 aka Jelly bean at Google I/O 2012. This wasn’t a revolutionary shift like it was with Gingerbread to ICS but packed a lot of improvements. Biggest feature being Project Butter which aims to improve performance and response time to make it fluidic and make it faster than ever before.

Google came up with an application that is not just siri but which learns from what you like or what you do. The personal assistant that understands you.
Apart from this, Google have tweaked the home screen launcher and added some cool features like resizing widgets and then move it to wherever you want. The integrated Google search have been improved with some really good features. It now has offline voice search and natural speech dictation abilities.
There is also a new thing called Google now, which will give you detailed information about your surroundings like whats happening around, what all places to visit etc.
Chrome finally came out of beta and will be the default browser for the new mobile OS.
The camera app which was revamped in ICS have got even better now. The gallery is now integrated with the Project butter features making it so smooth.
One of the major changes is in the notification center. Alerts dynamically change their positions while updating. You can have the full view of an attached image and can +1 a post without leaving the notification center and can expand the alerts by using multi touch.

Jelly Bean will be rolling out to Galaxy Nexus, Nexus S and Xoom devices in mid July, along with the source code. Developers though, can start playing with the SDK starting today.