blinklink - The Party App - Add light to the party

blinklink party app uses bluetooth smart technology to allow smartphones to communicate with each other through flashing colours.
Use blinklink to find friends easily in large crowds, at concerts, and at festivals. Put your hands up, tap your screen to blink colors, and add light to the party. At events, turn on Music Flash and let the music’s rhythm or the VJ take control.

blinklink is currently available for iOS and Android, and is 100% free.