[Nexus 7 (2013) General] mhannigan:
This is the exact problem I just started having after a couple weeks of use. I don't think this is strictly a hardware issue. Today when it started doing this, I was laying on my bed typing and it slowed down to a crawl. It was accepting one out of every 3 or four key presses. If I touched for more than a couple of seconds, it would finally register, usually acting immediately as if it were a long press. At first I thought it might be related to Google Keyboard. I changed to a couple others with no change. In fact, the behavior was consistent throughout the GUI. And once this happened, it stayed the same - I put it on the bed, I held it in both hands, I squeezed it, I stood up on the carpet, I stood on the hardwood floor, I put it on the counter, I touched my elbow to my FiOS box and then to the light switch to make sure I was grounded, and I sat on the toilet. Nothing fixed it, EXCEPT plugging it into the charger. The symptoms disappeared immediately. What surprised me is that when I unplugged it, the symptoms returned immediately. I wanted to take advantage of having it in this state, to try to find out SOMETHING concrete - this is driving me nuts. I turned on some debugging options like CPU monitoring and some GPU options, turned off all Background processes, and set it to "Don't keep activities" to ON. Still no change at all. The experimenting went on intermittently for about 2 hours without a change in behavior. I was at least able to nail the exact behavior down to it taking two to three seconds to initially respond to a touch. If I left my finger on the screen I could draw like a madman and color in the entire screen without missing a pixel.

I opened the Nexus 7 II Screen Test App from Google play - the one that displays different test patterns, (https://play.google.com/store/apps/details?id=com.gombosdev.nexus7tester) some of which invoke ghost touches, app switching, and other weird stuff. (it requires no special privileges, so I'm 99% sure it's legit) I picked a couple of patterns that didn't affect the screen, then I picked (I think) pattern 1 and the screen went bonkers (in a somewhat predictable way even though it looks random). I could see ghost presses really fast on the software buttons, Google Now opened, it went back to the desktop, back to the app, and then FC. I opened the app again, selected the same pattern and the exact same thing happened.

After that I didn't re-open the Screen Test App, but went back to Chrome. The tablet was suddenly ultra responsive. I mean snappy - no problem at all. I am absolutely certain that the app I'm talking about was not running prior to that - in fact nothing was since I had turned off background processes. I turned off all debug options so processes could run again. Still, the tablet is absolutely screaming right now and it's been about 4 hours since then.

Unless there was some extraordinary coincidence, the screen test app "crashing" this display (not sure what else to call it) completely resolved the problem at least for now. Plugging it in had solved the problem while it was plugged in, but whatever happened when that app displayed the test pattern that made the screen tank, caused it to start working properly again. Because none of it is very logical, this is the first time I had some time to actually test various things without rushing to try to get it working and then not knowing what fixed it. Since I can't make it start acting funky, I'll have to wait until the next time it starts doing this to see if I can reproduce it.

This seems weird enough to be consistent with people opening up the tablet looking at the cable, closing it, and then it suddenly works. It's tough to nail down if it was opening it, touching the cable, re-seating the cable, closing it, etc that made it work. This time, I'm certain that it started to work immediately after the screen displayed from the test app caused it to freak out. Not quite enough to establish cause and effect, but it's closer than I've been so far. Any thoughts?