LinageOS is a free operating system for smartphone and mobile devices that is based upon the Android mobile platform. As an open source platform, LinageOS can be edited and tweaked by users to create the best possible mobile experience for your smartphone. The popular open source code is constantly being developed and offers features and options not available in official firmware from most other mobile vendors. Though its open source, LinageOS is reliable and stable and word on over 178 different phone models with over 1.6 million installs. It can be downloaded directly from the official website for free.