Nexus 4 Screen Replacement - Would missing shielding tape or double-sided tape cause issues? I recently swapped the screen assembly (LCD + Glass + Digitiser + Metal Frame) for my Nexus 4. It was done similarly to this:

http://www.youtube.com/watch?v=MFzbfeY_xTQ

I swapped one phone out, and it appears to be fine. However, on a second phone, I noticed some issues:
 - Sometimes, when it boots up, the LCD seems fine, but it doesn't register touch inputs. At first, I thought this was a dodgy USB charger I had - when plugged in to that, it would seem to register random touch inputs all over the screen. However, I've also seen it simply not register any touch inputs when it's not plugged in.
 - Wifi reception seems a bit off - it will see WiFi networks, but it didn't connect successfully. I still need to verify this (it may be related to congestion/interference, but I'm not sure yet).
 - Battery seems to drain a bit fast - I also need to verify this, and quantify it.

During this second repair, a few things went funny (I was tired and rushing it...not a good combination)

Firstly, the battery was very hard to get out, due to the adhesive bonding it to the case. I really had to pry it, and the battery flexed a bit during the removal. I did attempt to get it into reasonable shape afterwards, but not sure if this caused any issues?

Secondly, there is some metallic shielding tape over one component, that also wraps around underneath:



I was able to scrape some of it off the top of that connector, and transfer it across, but the tape also wraps around underneath the connector as well, sitting in between the connector, and the metallic part underneath. I didn't replace this tape with anything.

I don't know if this would cause any issues.

Thirdly, there is some silver mesh double-sided tape that sits underneath this component, sticking it to the case:



I wasn't able to transfer all of this across, and so I guess I'm sort of relying on everything fitting together to keep this flex cable in place.

My question is - could any of the issues I've seen be caused by the missing tape (metallic shielding tape and the mesh double-sided stuff)?

If so, does anybody have any specific recommendations for where I can buy tape to replace them?

If I do have to replace the battery, I suppose I'll need to buy some clear double-sided tape as well to stick it back to the case. The replacement screen assembly I bought had some, but that'll be gone now if I remove the battery in there now.

Any other thoughts on the symptoms?
The chip that's missing the shielding is part of the digitizer; it is responsible for interpreting changes in the electric field of the screen and figuring out where your finger currently is, and what location of the display you've touched. Without shielding it won't work properly, or as you've seen.. at all. Get some here.. any decent RF shielding tape ought to work.

The conductive foam stuff is called an EMI gasket, and is used to isolate RF noise sources by "trapping" noise sources in specific regions. It more or less works the same as a traditional gasket, physically blocking the path. Measure the old piece if you can, or just guesstimate the size required.