It didn't take long at all for developer Chainfire to sort out a root method for the new Android 5.0 Lollipop. After handling a few issues with changes to the SELinux kernel module, Chainfire pushed out an update to his popular SuperSU root app.
It's time. You've experimented with apps from the Play Store, you've switched your lock screen, and maybe you've taken different launchers out for a spin. If, throughout your tinkering, you've found yourself chanting, "More. More. Give me more!" then now is the time. It's time to root.
Okay, so you're rooted and need to return your Nexus 5 to its stock firmware. Whether it's because you need to send your phone in to the manufacturer to fix a defect or you just want to use the device's over-the-air updating feature, unrooting and returning your Nexus 5 back to its fresh-out-of-the-box state is a fairly simple process with the right tools.
The flexibility within Android is pretty amazing. Unlike iOS, you can make a lot of modifications with nothing more than a download from Google Play, but to really step up your softModder game, you'll need to go a little further.
When you enter the softModder realm by rooting your Nexus 5, you open up an exciting world of possibilities and deep customizations for your device. Among other things, it gives you the ability to flash custom ROMs which, individually, act as entirely different operating systems that can vastly alter your user experience.