The latest version of the Android operating system, known as Jelly Bean (4.2), has started rolling out to some Google Nexus handsets.
Some Twitter and Google+ users started reporting that the new version of the OS is being pushed out as an over-the-air download in the early hours of Tuesday morning.
"Just checked my Galaxy Nexus and it's downloading 4.2...Aww yea," 'Jason Paul' posted on Twitter.
Shortly after, the download appeared on the popular developer and modding site XDA Developers. The download is the 'Takju' version of the OS, meaning that it is the GSM build for Nexus handsets bought directly from Google.
The timing of the update is surprising, given that the only devices to arrive running Android 4.2 as standard (the Nexus 4 handset and Nexus 10 tablet) just went on sale, on Tuesday. Network-locked versions of smartphones often take longer to receive operating system updates, as the build needs to be tweaked for each operator and then run through a testing process.
Jelly Bean Android 4.2 brings a revamp of the Siri-like Google Now voice control functionality, a new Gesture Typing feature similar to Swype and a 360-degree photo-capture mode called Photo Sphere.
People can check to see if the update is ready to download over the air by checking for updates in the system settings on their handset.