[LG Optimus G (International)] PsychoGame:
First of all, I'm not the maintainer of this device, I just created this thread to have a central place where everything related to this rom can be discussed, and give other users with problems good support

WARNING! This ROM is for the E975 variant only!

CyanogenMod is a free, community built, aftermarket firmware distribution of Android 5.1 (Lollipop), which is designed to increase performance and reliability over stock Android for your device.

/*
* Your warranty is now void.
*
* We are not responsible for bricked devices, dead SD cards,
* thermonuclear war, or you getting fired because the alarm app failed. Please
* do some research if you have any concerns about features included in this ROM
* before flashing it! YOU are choosing to make these modifications, and if
* you point the finger at us for messing up your device, we will laugh at you.
*
*/

CyanogenMod is based on the Android Open Source Project with extra contributions from many people within the Android community. It can be used without any need to have any Google application installed. You will need to provide your own Google Applications package (gapps). CyanogenMod does still include various hardware-specific code, which is also slowly being open-sourced anyway.

All the source code for CyanogenMod is available in the CyanogenMod Github repo. And if you would like to contribute to CyanogenMod, please visit the Gerrit Code Review. Your changelog is whatever was merged into gerrit.

Current known Bugs (Nightly 03/06/2015):

SIM Pincode doesn't get accepted even though the code is correct. The bug report on this issue can be found here. The currently known workaround for this bug is also found in the FAQ section in this topic.

If you encounter a bug please tell me so I can try to track it down and tackle the problem! (Just leave a message here, or file a bug report using the button above.)

CM-12.1 Install Guide

Note: CM for Optimus G International is provided with no warranty. You are installing this software at your own risk. You may be violating your warranty.

Download CM-12.1 and gapps-lp (optional) zips and put in /sdcard

TWRP 2.8.6.0 (E975): twrp-2.8.6.0-geehrc.zip

Temporary use this link to download the nightlies (Need to rebuild recovery to accept the CM provided zips):http://www.mediafire.com/download/lao5nw89s1mrman/cm-12.1-20150603-NIGHTLY-e975.zip

E975: https://download.cyanogenmod.org/?device=e975&type=nightly

UPGRADE REQUIRED

gapps version 20150602

MD5SUM: eeb01bdad581fc02133dda28d08ad574

Please verify the md5sum to be sure you got the right one.

Before you install CM-12.1: Preparation

(First three are optional. If you want to start fresh, these can be skipped)

Install AppBak from Market, run it and save a list of all your apps.

Install SMS Backup and Restore from Market, run it and backup your SMS history.

Install Call Logs Backup and Restore from Market, run it and backup your call log history.

Boot into TWRP Recovery (Instructions below). Make a full backup. You will need this backup later if you decide to go back to your previous ROM and data.

WARNING: Many apps will Force Close crash if you restore data from a previous ROM.

Install

Use TWRP Recovery 2.8.6.0. Install Howto:

Make sure you have rooted your current Android ROM with any of the methods floating around this forum.

Install Freegee from the PlayStore

Run Freegee and accept root permissions

Make a EFS Backup and store it somewhere safe (Freegee saves it in the internal storage by default, you should copy it to a USB drive for safekeeping)

Install CWM from Freegee, and if asked use the Mako unlock method to unlock the bootloader.

Boot to CWM Recovery

Power off your device.

Wait a few seconds.

Boot to bootloader by pressing the Volume UP and Power Button at the same time for 2-3 seconds until the Google Logo appears on the screen.

In bootloader choose 'Recovery Mode' using volume up/down buttons to swap selections, and power button to select the highlighted option

Release the buttons and press them again until the Recovery Screen appears.

Choose 'Install zip', Select 'Choose zip from /sdcard', browse to where you saved twrp-2.8.6.0-geehrc.zip and flash twrp-2.8.6.0-geehrc.zip

Reboot to Recovery from the 'Advanced Menu'

Warning: Only use this recovery to flash CM-12.1. Otherwise, you risk bricking your phone!

In TWRP choose 'Wipe', then 'Swipe to Factory Reset' and go back to the main menu.

Choose 'Install', browse to where you saved cm-12.1*.zip, select the cm-12.1*.zip and 'Swipe to Confirm Flash'.

(Optional) Flash gapps*.zip. You must flash gapps after every upgrade to CM-12.1 since /system is formatted, wiping your previous add-ons.

Reboot phone.

After you setup your Google account, reinstall the three apps from Market in order to restore most of your apps, call log and SMS history.

Warning: Do not restore backup data of system apps!

If you restore a bad backup with cached settings in telephony.db in data/data/com.*.*.telephony it can break MMS.

It seems that restoring backups can also break Calendar sync.

Upgrades

Upgrades from previous versions of CM-12.1 are the same process as install, except you do not need to wipe anything. Contrary to popular belief, you do not need to even wipe cache and dalvik-cache when upgrading between CM-12.1 versions. You only need to wipe if you are doing a major upgrade, switching to a different ROM entirely, or attempting to fix bugs caused by bad backups or corrupt app data.

Useful Links:

CM12.1 Nightlies Changelog E975

E975 CyanogenMod wiki

Jira issue tracker

Source repos:

https://github.com/CyanogenMod/android_device_lge_e975/tree/cm-12.1

https://github.com/CyanogenMod/android_device_lge_gproj-common/tree/cm-12.1

https://github.com/CyanogenMod/lge-kernel-gproj/tree/cm-12.1

https://github.com/TheMuppets/proprietary_vendor_lge/tree/cm-12.1/e975

FAQ:

Q: How the heck do I get root?

A: Goto Settings and About Phone. Tap Build number 7 times. Go back and enter

Developer options. Change Root access to desired method.

Q: How to get around the PIN not accepted bug for now?

A: A workaround for this bug, until it has been worked out, is to just disable the PIN security for your SIM Card.

Other Issues?

Use this for obtaining logs.

Credits:

The CyanogenMod team would like to thank everyone involved in helping with testing, coding, debugging & documenting! Enjoy!

XDA:DevDB Information

[E975][ROM][Official][5.1.1] CyanogenMod 12.1 for Optimus G International, ROM for the LG Optimus G

Contributors

PsychoGame

ROM OS Version: 5.1.x Lollipop

ROM Kernel: Linux 3.4.x

Version Information

Status: Nightly

Created 2015-05-24

Last Updated 2015-05-24