I have a Nexus 4 16GB stock on 4.2.
It is experiencing a ghost/phantom touch issue, as you can see here:
http://www.youtube.com/watch?v=f61TPtL4WBk
This doesn't happen all the time, but it does happen regularly (every 5-10 minutes) in Chrome, Dropbox, the stock Settings app and an app I'm developing. It doesn't happen on the homescreen, though - at least not that I've noticed. It may happen only when the device is warm, but I can't really tell as it's not that consistent.
I tried updating to 4.3 (using the standard OTA) and the touchscreen becomes completely unresponsive, like this:
http://www.youtube.com/watch?v=QSt5GFSTr0E
In this state you can't even unlock the phone, though it is responsive as you can see. I also tried sideloading 4.4 onto the phone, and this didn't work. I tried rebooting (by holding power for 10 seconds), going into fastboot and wiping the phone and nothing would enable the touchscreen to come alive.
I then restored the phone back to stock 4.2 (using instructions from here) which allows the touchscreen to work, but the original ghost/phantom touch problem remains.
Any ideas please?