While a lot of units are still waiting on the official OTA release of Google's newest operating system, Android M also known as Android 6.0 Marshmallow, CyanogenMod has revealed that CyanogenMod 13 (CM13 nightly) is already running Marshmallow and available for download to selected smartphones including LG G3..

According to International Business Times, the Android Marshmallow is bound to be released in mid-December starting with Poland and later to other regions. Based on the previous roll-out patterns, it will take another month or two for the firmware to reach all LG G3 units around the world. But if users want to try exploring the newest update now, they could install the CyanogenMod CM13 series custom ROM, developed by Tim Klein (aka cuzz1369).

However, they should keep in mind a few reminders and prerequisites before installing the custom ROM. The new Android 6.0 Marshmallow CyanogenMod [unofficial] CM13 custom series has to be installed on LG G3 (d85x, ls990 and vs985) models only. If installed to other devices, the units may get bricked. The device should also be rooted before going ahead with custom ROM installation. Apart from that, they must remember that upon installation of the custom ROM, the company's warranty will be voided. 

Furthermore, the installation of custom ROM needs clearing of memory in the phone, so owners of G3 need to make sure to back all the data by installing Clockwork Mod (CWM) Recovery/ TWRP in the smartphone. The USB driver should also be installed on the PC or else the device (LG G3) will not be recognized by the computer. Lastly, it is advised to have at least 80% battery so that the installation won't be interrupted.

Here are the step by step process on installing the CyanogenMod 13 custom ROM for LG G3 (via International Business Times).

The first thing to do is to download the CyanogenMod [official] Android 6.0 Marshmallow CM13 custom ROM nightly and Google Apps files to the PC then connect the LG G3 to the computer using the USB cord. Place the Android M zip file and Google Apps .zip file into the phone's SD card memory, turn off the device and disconnect it from the PC after.

The next thing to do is perform the regular Recovery Mode by press holding Volume Down and Power button. After entering the RECOVERY mode, users should clear the phone memory by choosing 'wipe data/factory reset' option.

After that, they have to clear the cache memory by selecting wipe cache partition, return to ClockworkMod recovery, choose advanced and tap wipe dalvik cache. Once done, come back to main recovery screen, tap install zip from SD card, choose zip from SDcard,  go to Android M ROM .zip file and enter the installation process. 

To install Google App, the same procedure should be applied.  Once set, navigate to '+++++Go Back+++++' and re-start the handset by opting reboot system now that can be seen in the recovery menu.

Meanwhile, aside from the LG G3, Latin Post cited other devices that can now be update to Android 6.0 Marshmallow via CyanogenMod custom ROM. The list includes, OnePlus One, Nexus 7, Moto X 2014, LG G4, Samsung Galaxy Tab Pro 8.4 and LG G Pad 7.0.

If one is not familiar with CyanogenMod or flashing custom ROMs to unlocked Android devices, this Android 6.0 Marshmallow update release is not advised. CyanogenMod custom Android ROMs needs not only unlocking the bootloader on handsets before starting the installation which could void factory warranties, but also some technical skills and knowhow.