During its opening keynote at the Google I/O developer conference this morning, Google announced the next major release of Android OS, dubbed “Jelly Bean.” Android OS 4.1 builds upon the work Google began in Android OS 4.0 (a.k.a. “Ice Cream Sandwich”), and introduces a new set of back-end tools, dubbed “Project Butter,” to improve performance and stability. Project Butter brings improvements to UI performance with “VSync” technology, triple buffering, and touch responsiveness, which makes the CPU begin working immediately after touching the display.

Other improvements in Android OS Jelly Bean:

• Improvements to home screen managements – icons and widgets will automatically move and resize depending on the location of other icons and widgets
• The keyboard has an improved dictionary and will now attempt to predict the next word that will be typed
• Voice typing now works offline with U.S. English support at launch and other languages coming soon
• 18 new input languages
• Improvements to Camera – review photos you’ve taken quickly using swipe and pinch gestures
• Improvements to Android Beam – send a photo or video by tapping two devices together; pair an Android phone with an external Bluetooth speaker by tapping the device to the speaker
• Improvements to notifications – built-in tools are now supported (example is a missed phone call: return the call directly from the notification); drag down with two fingers on the notification to reveal the built-in tools
• Improvements to Google Search – Knowledge Graph support; voice search is faster and understands natural language better
• “Google Now” – uses your search history, calendar events, previous locations to show information important to you (example is showing a map with traffic conditions on your way to work)

Android OS Jelly Bean will be rolled out as an over-the-air (OTA) update to Galaxy Nexus, Motorola XOOM, and Galaxy S users in July. Developers will be receiving a preview SDK today.

Finally, Google also introduced the Platform Development Kit (PDK) for Android today. The PDK is released to hardware developers two or three months before a new Android release is rolled out to the public, and includes low-level APIs and source code that can be used to port Android to new hardware.