☆Please notice this app require Xposed Framework.
☆I do not encourage you to use Xposed Framework unless you know what you are doing.
You will get notify when app(or people?) open your camera on mac.
You will get notify when app using your gps on phone.
But why would you not get notify when app open your camera on phone?
So use this Xposed module and get notify and green led when app open your camera.