Sony has started rolling our Android 4.1.2 Jelly Bean update for the Xperia SL and the Xperia Acro S. Sony Xperia Ion is next in line to receive the update, you can check if the update is available on your phone by going into software updates, or you might see an OTA update notification. Other than that you can always update through Sony's PC suite for your Xperia device.
