[Nexus 4 Q&A, Help & Troubleshooting] louis993546:
I post this on Google Product Forum 2 days ago. Hope it helps

https://productforums.google.com/for...Q/wDzRUm4b2UsJ

(updated 29/11/2014)[not perfect but it is a SOLUTION]

The idea of this is to downgrade your nexus 4 without wiping your data, which means stuff you will need includes:

1. adb and fastboot on your computer (I am using mac but you can find it on windows as well. There are tones of website and forums telling you the latest method of getting it onto your computer)

2. factory image of nexus 4(I use 4.4.4, since that's what it was. I don't have the time and energy to try to do the same thing with lollipop. you can try can leave a comment).

update: do NOT try to flash 5.0 rom using this method. You will be stuck at boot loop again

3. usb cable

4. nexus 4 with unlocked bootloader(the process of unlocking bootloader will wipe your device)

5. computer

steps

1. unzip the factory image (something.tgz)

2. for me, after unzipping the .tgz, I still find another .zip inside. unzip that too.

3. hold vol+, vol-, and power button simultaneously to enter fastboot mode

4. open terminal(mac)(it would probably be cmd for windows)

5. connect your nexus 4(in fastboot)

6. to make sure it connect successfully, type "fastboot devices". if something like "005040c0d54bb291	fastboot" appears, you are good. Otherwise, try reconnect your device/boot to fastboot again/use another usb cable

7.now we need to tell the terminal to navigate to the location of the unzipped factory image. to do that, i suggest you put the unzipped folder to somewhere easy to find, like desktop. these are some commands to help you navigate:

"ls" allows you to look at whats inside the current directory of the terminal. For example, this is the output after typing "ls" for me:

some folder	Photos

nexus4image.tgz	how many folders do you have

5.zip	occam-ktu84p

more folder	occam-ktu84p.zip

after knowing where you are, use "cd" (below) to go to your folder

"cd" means change directory. For example. "cd Photos" will brings me to the "Photos" folder. And then if I type ls, I will see a whole bunch of photos in my photos. If you go to the wrong folder, type "cd ..", and it will bring you back to the previous folder.

8. flash bootloader.

enter the following command, BUT REMEMBER TO CHANGE THE NAME TO FIT YOURS(DIFFERENT VERSIONS HAVE SLIGHTLY DIFFERENT FILE NAME AT THE END(type ls first to help you type the correct name)

fastboot flash bootloader bootloader-mako-makoz30d.img

9. reboot bootloader. just copy and paste

fastboot reboot-bootloader

10. flash radio

enter the following command, BUT REMEMBER TO CHANGE THE NAME TO FIT YOURS(DIFFERENT VERSIONS HAVE SLIGHTLY DIFFERENT FILE NAME AT THE END(type ls first to help you type the correct name)

fastboot flash radio radio-mako-m9615a-cefwmazm-2.0.1701.03.img

11. reboot bootloader. just copy and paste

fastboot reboot-bootloader

12. flash system

system.img is located inside the zip, use ls to help you navigate. This steps takes the longest time, total time on this step is 87 seconds while the others are less then 1 second

fastboot flash system system.img

13. flash boot

boot.img is located inside the zip, use ls to help you navigate.

fastboot flash boot boot.img

14. flash recovery

fastboot.img is located inside the zip, use ls to help you navigate.

fastboot flash recovery recovery.img

15. format cache(not the memory, so everything should be fine)

fastboot format cache

16. reboot and wait

this will reboot your device. You probably have to wait for a while to initialise all the apps. after than you are good to go!

fastboot reboot

credit: my friend for giving me this idea + http://xdaforums.com/nexu...image-t2010312 + HelpMyNexus