Samsung GT-I9506 Quick Start Manual page 12

Basics
Air Gesture
Use this feature to control functions without touching
the screen.
The device may not recognise your gestures if
you perform them too far from the device or
while wearing dark-coloured clothes, such as
gloves.
12
Quick glance
When the screen is turned off, move your hand above
the sensor to view notifications, missed calls, new
messages, time and date, and more.