Xperia Z2 receiving firmware update – enhanced call quality and better performance
Sony also claims that this update brings improved touch functions, performance, and bug fixes. Some users already claim that the Tap to wake function is working much better and that performance in general is more responsive. The latest firmware tag is 17.1.2.A.0.314 and the push-out to phones in different areas is being sporadic and unpredictable. If you want it now, your best bet is to just download it from Sony and install it on your phone via the USB cable and the official PC Companion program.