I been having Xperia Z Ultra and I don't have a serious problem with the device. but there is a bit problem on the task (notification) bar movement! actually when I push it down sometimes it doesn't come down quick and even completely, then I have to tap on back or home and do it again!!! let me know what is the problem and what's the solution??!
You can download a touch test application from market to check whether touch works fine first. If yes, maybe SW issue, try to reboot your device. Otherwise, maybe it is due to protective flim or touch panel issue.
