[LG G Flex 2] Iron_Overheat:
(ATTENTION: Using this guide is your choice. I am not responsible if your phone gets bricked. All I'm doing is sharing my results so people can enjoy a better experience on their G Flex2, I do not know if this guide will work in anyone else's phone, I only know it worked on mine)

Hello, and welcome to my guide :). I'm going to guide you through all the process I went through to install mods that will tweak your experience. The tweaks and mods used, are, as follows:

Audio Enhancement [Viper4Audio (credits to: users zhuhang and guitardedhero) Dolby Atmos (credits to: users guitardedhero and worstenbrood) and a modified mixer_paths profile (credits to: users paris07121978 and soosoolhastam)]

Camera Enhancement [modified camera_config and media_profiles (credits to: user jacksoncolocho)]

Screen And G4 Style-Tweaks [Flash-Mods (credits to: user bountyman334)]

Better Performance and Less Heat Output [modified thermal-engine-8994 (credits to: user probaina) tweaked interactive governors (credits to: users soosoolhastam and soniCron)]

Widened Scope of Phone Modifications [Xposed (credits to: user rovo89)]

Latest (Lollipop, Marshmallow on a locked bootloader is not rootable yet) Software Rooted Image (as of 5th of June, 2016) [15e rootedsystem image (credits to: user kevin3688)]

(I'm so sorry if I let anyone out, if I forgot to credit someone, please reply and I'll add him/her)

TL;DR, here's the guide:

1. (If you haven't already) Flash this image (https://drive.google.com/file/d/0B0UblGbOPFYBT2RERDZKcUhqcnM/view) on your phone, with this guide (http://xdaforums.com/g-flex2/general/lg-h959-v15a-rooted-andriod-5-1-1-t3178517). Note that that flash command works for the 15e image. Now you have the latest software version.

2. Download and Install (on your phone) FlashFire, from the google store (yes, from the google store, not the old 0.24 version).

3. Download and install Stericon's busybox from the play store.

4. Download XposedInstaller.apk into your phone and also download the zip file (the one you'll flash with FlashFire), which has to be from sdk22 (that's for android 5.1.1) and from arm64 (http://xdaforums.com/showthread.php?t=3034811). Make sure to download the latest one. Now open Flashfire and flash the zip file (+ button, tap on flash zip or ota, select the zip file to the downloaded location, and uncheck mount read/write, then tap on flash). Afterwards, install the downloaded XposedInstaller.apk on your phone and open it. You are now able to use Xposed, which is a unique framework that allows you to download modules, which are "apps" that can change your phone in a lot of ways, way more than a regular app, I think. To install modules, open the XposedInstaller and... you'll figure it out.

5. Downgrade your flashfire app into the 0.24 version, by uninstalling it and installing this version instead (http://flashfireapk.com/flashfire-0.24.apk).

6. Flash the mod (same thing as before, but now there's only the auto-mount option, don't check it) provided by this thread, look for the h959 link (http://xdaforums.com/g-flex2/development/dec-21-stock-lollipop-flex-2-ls996-t3275531). Download it (on your phone) and flash it with FlashFire (it might take a while). Now you should have a slightly better screen, G4 design changes and other tweaks to your phone.

7. Uninstall flashfire 0.24 and install the version from the google store again.

8. Download the Dolby Atmos zip file (http://xdaforums.com/android/apps-games/mod-dolby-atmos-t3109446) and flash it with FlashFire (same thing as before, now there are more options again, uncheck mount read/write again). You should now have a dolby atmos app on your app drawer, it uses an intelligent equalizer and other cool stuff to make your audio sound better. Tweak it to your liking.

9. Download the zip file "ViperAtmos x (x represents the latest version, 5.5 as of now) sony beats edition" (link: http://xdaforums.com/android/software/viperaudio-viperatmos-3-8-sq-driver-t3289075) (that "sony beats edition" is not completely necessary, so if in a future version it's not there anymore, don't worry about it). But don't flash it. Instead, copy the content of that zip file to your root folder (mount the folder as read/write with your file explorer and overwrite what's already there) (the lowest/highest folder on your phone, it's not accessible via pc, only via a root browser). The folder can also be called "system(root)" or a hashtag or just "/", don't confuse it with the folder named root that is inside "/" or the folder "system" that is also inside "/". If any files couldn't be placed, like for example audio_effects.conf, try finding that file (it's in "vendor/ect", "system/etc" and "system/vendor/etc") and mount that file read/write, now try copying and pasting again, if it doesn't work again try rebooting and trying again. Open the V4A (V4A stands for Viper4Android) app, it may say to install drivers or it might be already installed, if it says install drivers tap on ok. It will say drivers are installed, so reboot.

10. Download and install SE Linux Mode Changer (http://xdaforums.com/showthread.php?t=2524485), give it root permission and change the mode to permissive. Now Viper4Android and Dolby Atmos should be working together. Viper4Android is an audio tweaking tool that enhances your listening experience, and gives you a range of customization to do so. Tweak it to your liking.

11. Download the following file: http://xdaforums.com/attachment.php?attachmentid=3566699&d=1449390187 (delete the mixer_paths from that zip file). Also download the mixer_paths file from this thread (http://xdaforums.com/g-flex2/development/surround-mode-h955-t3376881), look for the latest post of the user "soosoolhastam" on that thread, the one where he uploaded his modification of the mixer_paths file. Also download the thermal-engine-8994 file from Probaina here (http://xdaforums.com/g-flex2/general/thermal-throttling-hotplug-settings-t3106165), it's in a reply he made to his own thread, it's on the first page. Now that all those files are on your phone, use a root text editor (the only one that worked for me is the app QuickEdit) to copy the content of all those files, and replace the content from the files (with the same name) on the folder /etc. Don't replace the files, since that "broke" my phone, just replace the text content of those files with the content of the files you downloaded, that have the same name. Now you have unlocked 60fps on your camera, your photos are now all stored with 100% quality, your audio has a higher volume and it's more surround, and your phone should heat up less.

12. Download the file "init.qcom.post_boot_xxxxxx.zip" (again, the Xs represent whatever the latest version is, choose the biggest number, not the "original" version) from here (http://xdaforums.com/g-flex2/general/tweak-interactive-governor-lag-battery-t3371210). Extract the file and navigate to the folder GhostPepperVx (x=latest version) (you can choose from the other folders if you want, they have different cpu governors, if you want to try another one) then copy the file "init.qcom.post_boot" inside that folder into system/etc. Make sure your phone is not overheated (since that changes things).

13.Wipe dalvik cache with flash fire to cleanup your phone after all the flashes and stuff. There. Now your phone should be better in every way!