These updates are basically bug-fixing updates and do not change the Android version installed in the phones.

Android 4.1 Jelly Bean update (for Xperia’s three devices) brings several tweaks and developments through the system. In the hardware and user interface segment, users can long press the home key to launch Google Now feature. The quick launch button has been improved for instant launch. Quick double-press shows the list of recently used applications. The volume up button responsiveness has also been improved.

These improvements are expected to make the Xperia devices deliver better performance.

JPN