Sony was the only one of the three major Android OEMs that didn’t release a Google Play edition of its flagship device, but that does not mean Android purists and enthusiasts are left out of the game for good. Instead, they have just received one more pure Android ROM that begs to be tested: it’s an Android 4.3 Jellybean build that was ported from the recently leaked ROM for the Google Play Edition phones.
The project is maintained by XDA Recognized Developer Taylor_Swift, who has done a great job with the port, as most of the functionality is there, save for some bugs. Speaking of bugs and missing features, the ROM lacks root, and Chrome tends to force-close. Nevertheless, the developer provided methods of fixing these issues, so that shouldn’t be the major problems. The ROM, however, is still in early beta stages, so don’t expect it to be a good enough daily driver.
If you feel adventurous, you can grab the download and try Android 4.3 out on your Xperia Z from the official thread on XDA-Developers.