Though there are various options to be explored when you choose to root your Android device, one great advantage is that you can install a custom ROM. However, it is easier to make individual changes on your general OS. But with a new custom ROM, there emerges out a plethora of new features, new themes, and even updates to devices that were abandoned by their manufacturers.
Over the years, CyanogenMod has maintained its supremacy in the domain by establishing itself as the most popular ROM. Its biggest feature was its build on stock android along with a host of fabulous features. However, due to several complexities, the company decided to shut down its operations at the end of 2016, resulting in a bleak way ahead for its users. Now the good news is that the team working behind CyanogenMod has re-emerged itself with LineageOS, and you can give it a try.
For this, you can visit the LineageOS downloads page and check the devices that support this version. According to various sources, a few of supported devices are Nexus 6P and 5X, Samsung Galaxy S5, the OnePlus 3, and Motorola Moto X Pure.Given your device make & model, the ROM will be based on either Android 6.0 Marshmallow or Android 7.0 Nougat.
Before you give it a try, it is important to note that only experimental and nocturnal builds are available as of now. It simply means that those looking for a more stable version of the same need to wait for some more time. As developers have already been involved in testing new features, you may encounter some blemishes in these testing builds.
Once the testing will be over, the full-fledged version of LineageOS would be ready to rock you.