LG Optimus 90 is a mid-range Android smartphone. The L90 has a 4.7″ IPS LCD display, with a resolution of 540 x 960. It runs on a Snapdragon 400 1.2GHz quad-core processor and 1GB of RAM. It has 1GB of internal storage, an 8MP camera and HSPDA / WI-Fi connectivity. The LG Optimus L90 is powered by a 2540 mAh battery.
LG Optimus being a mid-range device, wont be getting official Marshmallow updates. However there is no need to worry as CyanogenMod team have developed CM 13 ROM running on Android Marshmallow. This ROM is known to perform better than stock ROM and offers more features. Follow the guide below to install it on LG Optimus L90.