Strobe led

Hi guys I was wondering if there's any kinda app out there which when the phone screen turns off a led strobe goes from left to right (like the knight rider kitt style).
I've tried all the kitt apps on play store non of them do what is like. I want the strobe to start automatically when screen turns off. Also changing colours would be cool. Either there's a app like this or I've given someone a idea to maybe design a app like this? I really think it's a cool idea.
Are there any apps out there like this?