Photography is all about finding the light. These days, light from some "device" is almost always available since we can't seem to put them down...and as it turns out, screen light is quite effective as a light source.
If you want to have some fun with screen lighting and color, there is an app called color screen that creates an effect almost like a softbox and will cast any color light on your subject.
ANOTHER TIP: In any photo situation, If you find yourself needing extra light on a subject, the screen of your phone will always provide more pleasing light than does the flashlight, which tends to be quite harsh and casts more shadows.
Have fun playing!