Soundyarn

Soundyarn is a platform that allows anyone to create, experience and share interactive location-aware audio experiences, called yarns, that augment the real world with sound.
The Soundyarn iPhone app lets you experience yarns where audio interacts with outdoors locations in sophisticated ways. These yarns can be anything from simple location-dependent audio stories to multilayered interactive outdoors sound adventures.
Use the Sound Throwster iPad app to create your own yarns!
Please note: Continued use of GPS running in the background can dramatically decrease battery life.