Are you an owner of a 2011 Sony handset and want to experience Kit Kat on your device? Thanks to the hard work by a team of dedicated ROM developers, several older devices are beginning to taste Kit Kat even though the manufacturer of the device has stated that they have no plans to upgrade legacy hardware.
The developers who are working on this task are part of a group known as the LegacyXperia Project and they are building their ROM on top of the popular CyanogenMod 11 base. The ROM has been ported to several 2011 devices including the Xperia Arc, Arc S, Neo, Neo V, Mini, Mini Pro, Active, Xperia Pro, Xperia Ray and Live with WalkMan. This is quite an impressive list of devices.
As usual, flashing custom ROMs is not without risk and this is no exception. The ROMs are currently not designed for everyday use and several features are missing or broken. These bugs will likely be resolved over time however the list of broken items is quite extensive and includes; broken FM radio, no 720p video recording, no USB storage, no HDMI out and Wi-Fi tethering does not work. The project's bug tracker seems packed with other device specific bugs and many users are also complaining of sporadic WiFi issues. Most of these are deal breakers to most so we cannot recommend installing this on your primary device.
If you consider yourself a brave individual, head on over to the project homepage and head over to the XDA Thread for your device. Be sure to read and understand all of the device specific instructions and bugs. I will repeat what I said above; do not install this on your primary phone.
This hard work and dedication goes to show how committed the Android developer community is. It does not matter if the manufacturer has end of lifed a device, chances are that it will get an unofficial ROM. Lets not forget that the Galaxy Nexus, HTC HD2 and even the grandfather of all Android devices, the Nexus One have all gotten (unofficial) Kit Kat builds.