LG Optimus G is LG’s late 2012 flagship phone. It is powered by quad-core Qualcomm Snapdragon S4 Pro processor. The speedy processor is backed by 2 GB of RAM, 32 GB of ROM, a 4.7″ “True HD-IPS+” panel, LTE connectivity, a 2100 mAh battery, and an 8 or 13 MP camera (depending on region). It originally came with ICS OS but it was upgradable to Jelly Bean.
The Sprint variant of Optimus G has received the CM 12 custom ROM. This ROM will upgrade the device to Android 5.0 Lollipop. Its a useful option as Optimus G is not scheduled to receive official Lollipop update. Follow the guide below.