Ok, I replaced the glass on my Galaxy S4 utilizing the following items.
* Prokit UV glue 3.5ml LOCA Liquid optical clear adhesive
* S4 glass lens
* Infrared thermometer
* Plastic razor blades
-=FROM AROUND THE HOME=-
* Heat gun (Ace Hardware)
* Standard screwdriver and spludger kit for smartphone repair
* Isopropryl alcohol
* Gauze sponges
* Lint free cloth
This was my first time and I learned the following things so I will share them here with you.
Like all the videos say, You need to go SLOW and really take your time separating the glass from the digitizer/LCD. The digitizer and LCD are pretty robust but if you don't go slow you can crack the LCD while separating the broken glass.
It would be VERY difficult using a heat gun without an infrared thermometer. The temperature of the glass fluctuated very quickly so I had to keep adjusting the distance of the heat gun from the glass to ensure the temperature stayed around 180-190 degrees F.
Use gloves! The glass and metal frame get very hot.
Once the broken glass was removed it was slow getting the residual adhesive off the digitizer. Take your time and use rubbing alcohol and gauze. The texture of the gauze seemed to facilitate quicker and more efficient removal of the adhesive.
I chose not to use the 2mm 3M adhesive around the border of the digitizer/LCD. In hindsight this was a mistake. I left the old adhesive in place since it appeared to be intact and still sticky. I should have peeled the old off and used the 3M.
Using the Prokit LOCA: I should have removed the digitizer/LCD from the chassis and followed similar methods employed in this video: http://www.youtube.com/watch?v=V-swd_s7J...
Since I didn't I got time air gaps around the edge of the screen, seen here: http://i.imgur.com/Df6F1RA.jpg
I had very few air bubbles under the glass and, again, this might have turned out better if I had removed the digitizer/LCD from the chassis.
I cured the LOCA by leaving the assembled unit in the sun for 15 minutes. I think that was enough time.
Since I had a second screen on my phone I only hooked the repaired screen up to the disassembled phone to test it. Here are some finished pictures.
Two additional problems. Since I used too much glue (I think) It went up into the space for the front facing camera and occluded the glass so I can't use the front facing camera.
It also leaked into the area where the back button and menu button are located. This made the buttons look a bit murky/dark, seen here: http://i.imgur.com/qcW4eVU.jpg?1
The HOME, BACK and MENU buttons work fine, the screen is as responsive to touch as before and looks great despite the free tiny bubbles and tiny air gap around the LCD (this isn't visible on the actual screen.)
All in all it wasn't that hard of a repair. It took about 45 minutes and if I have removed the LCD from the chassis, it would have taken longer but probably only 30 minutes more.
I hope that helps some of you.
!!! UPDATE !!! !!! UPDATE !!! !!! UPDATE !!! !!! UPDATE !!! !!! UPDATE !!! !!! UPDATE !!!
I couldn't find ANYTHING on the internet about removing the LCD and digitizer from the chassis so I just bit the bullet and did it. I used several plastic razors to slowly pry the LCD/digitizer from the chassis. I probably should have used the heat gun to soften the adhesive that was holding the LCD to the chassis, but I didn't. The layers of insulation that protect the LCD from the rest of the phone got a bit wrinkled. Nothing I probably can't fix before I reassemble the phone.
Here are pictures of the results:
The silver layers in the 3rd picture have a silver paste like residue. It reminds me of the thermal compound you put on a CPU before attaching the heatsink/fan. Something to keep in mind when reassembling the phone.
Bare LCD/digitizer in use:
Hope this sheds some light on removing the LCD/digitizer from the chassis.