You can turn your Windows Phone into an air traffic radar and then see airplane traffic around the world in real-time.
Flightradar24 Free Features:
. See planes move in real-time around the World
• Get flight number and callsign info for individual Aircraft
• Search for flights
• Augmented Reality View – identify the planes flying overhead by simply pointing your phone’s camera to the sky (On supported devices)
• See images of most aircraft