Software Plus

CyanogenMod 12.1 Android 5.1.1 Custom Rom has been ported to the LG Leon MS345! This comes in from XDA-Member AndroidAddict||AA with instructions on how to install this custom rom and running on your LG Leon MS345 (only). 
Note: Following this guide at your own risk. I’m not responsible for any damage.
Requirements:

• Root
• Unlocked Bootloader (must be on stock 10B)
• TWRP Recovery installed
• cm-12.1-20150714-UNOFFICIAL-ms345.zip
• GApps

If you want to install the CyanogenMod 12.1, follow the source link below, all steps been tested and is working:

1. Download CM 12.1 custom rom and gapps and save them to sdcard or internal storage
2. Boot into TWRP recovery
3. Wipe Data/Factory Reset
4. Wipe Cache and Dalvik Cache
5. Install CM12 zip via New TWRP
6. Install GApps
7. Reboot and enjoy!

Working:

• Almost Everything

Not Working:

• Battery is buggy
• Front camera recording
• CPU Frequencies sticking
• You tell me??

Source
LG Leon MS345 Phone Photos – LG Cell Phone Pictures