[LG V35 ROMs, Kernels, Recoveries, & Other Developm] hp79:
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EDIT 8/8/2022: This will probably wipe out your phone call capability. I didn't make a backup of some partitions so now it can't make any phone calls, although LTE data works fine. I spent few hours trying going back to stock US version Oreo but that did not fix my phone call issue. Whenever I try to call, it cancels the call showing "Call ended" immediately. So if you are unsure, do not follow this guide.

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Lot of the material is from @cmrntnnr post #1 on https://xdaforums.com/t/bootloader-unlock-and-root-instruction-no-octoplus-box-required.4052145/

I initially followed that but couldn't get it to work from Step 3 - installing Magisk and gave up there. I then realized even with root there is no custom ROM such as Lineageos so I reverted to stock V350ULM Android 9 / P.

I recently found that people are cross flashing to Korean version Android 10 Q so I went ahead with it as I really don't like how things are with this LG phone on Android O and P. Lot's of annoyances. I have an iPhone SE (2020) by the way as my main phone. My phone here is a V35 factory unlocked version from U.S. I had the Android 9 P (V350ULM20f_00_NAO_US_OP_0218).

Download firmware - V350NO30c_00_OPEN_KR_OP_0125.kdz

LG V350N(LMV350N) aka LG V35 ThinQ - LG-Firmwares.com

LG V350N download the firmware for free! Detailed installation instruction. Video review of the model and its features. User feedback and latest news.

lg-firmwares.com

(update in 2022/8/6 -- they have "V350NO30d_00_OPEN_KR_OP_0929.kdz" dated 2021/10/28. I think this is probably the last version they will ever have.)

View attachment 5250901

The LG mobile drivers, http://tool.lime.gdms.lge.com/dn/downloader.dev?fileKey=UW00120120425

Download Dev-Patched LGUP (LGUP_DualMode.zip) thanks to @tecknight

Download https://androidfilehost.com/?fid=11410963190603845019

Once you extract the zip file, I installed "LGUP_Store_Frame_Ver_1_14_3.msi" and then also ran "SetDev.bat" as Admin to get it working. To run it as admin, right click on it, then click "Run as administrator".

Afterwards, you just double click "LGUPD.exe". You don't have to run this one as admin. The other one (LGUPU.exe) is a more simple version that doesn't have the advanced option, so don't use that.

Power off your phone. Hold the "volume +" button (it's the one on the upper of the two) and plug in the USB cable. Your phone should almost immediately go to Download mode. You can let go of the "volume +" button now. On the LGUP, you should see the following screen. At first, select "PARTITION DL" and then "Start". Select all of the details. I tried leaving the modems but after done it was causing errors so I had to redo this step.

View attachment 5250903

Once done flashing, I actually went ahead and did another flashing, this time I selected the same image and did "REFURBISH" mode to make sure it's flashed correctly. Once done, the phone rebooted and I was greeted with Korean language welcome screen, where you can change the language.

I'm a Korean so I'm comfy with Korean showing up once in a while but I prefer keeping everything in English.

After all this, I'm really liking this version. There is a default stock black theme which is really nice. You don't have to download one Theme Store or whatever that was.

The camera works fine, and there is an obnoxiously loud camera shutter sound but I'm fine with that.

Dialer will show Korean characters under the numbers along with alphabets. You can enable automatically record all calls. There are also several other areas where it'll remind you that this is a Korean OS, so if you hate seeing foreign characters here and there, it's probably not for you.

Phone calls are working fine, LTE is working fine. Not sure if VoLTE is working or not.

There is no Wifi-call. I guess in Korea wifi call is not needed as there are good cellular signals everywhere.

LG Pay is installed, but it won't work because I have a SIM from U.S. Installing Google Pay, I was able to add a credit card for NFC payment, so I think that works too.

Keeping it in Airplane mode and rebooting, you still get the nag screen about Airplane mode.

Not sure what else doesn't work.

(update in 2022/8/6. I used a Korean SIM while visiting Korea on this phone. Once I came back to U.S. tried using a U.S. SIM. Data worked fine but all phone calls would not work. Not sure if there's some issue with my SIM - ATT based Tracfone or something else.)

Here are some stuff to uninstall after enabling Developer mode, through adb shell.

Start adb shell

#Facebook crap

pm uninstall -k --user 0 com.facebook.system

pm uninstall -k --user 0 com.facebook.appmanager

pm uninstall -k --user 0 com.facebook.services

#LG Pay

pm uninstall -k --user 0 com.lge.lgpay

pm uninstall -k --user 0 com.lge.lgpay.qlauncher

#LG Assistant

pm uninstall -k --user 0 com.lge.lgassistant

#TV

pm uninstall -k --user 0 com.lge.tdmb