You mean Always On?
Not sure which Android version/ROM your running but guessing if the feature is not built-in under display settings then you'll just need to use an app from the play store eg. Light flow LED controls
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality.
Are you a developer?
Copyright © xda-developers. Hosted by Leaseweb