New iPhone app sends digital content with chirp

A distinctly electronic twittering is the sound of a new iPhone application that might change the way we share information with each other.

Chirp, which has been recently launched, is a new service that allows people to share digital content like web pages, pictures or video, by playing short tunes to each other.

It works much like any other social media service used to upload whatever you want to share, but Chirp notifies other people about what you have shared - it turns information about your upload into a sequence of 20 musical notes, played rapidly through your phone's speaker, which can be heard and decoded by any other Chirp-equipped device within earshot.

That device then retrieves the shared information and displays your picture accordingly.

While there are already numerous ways for people to swap stuff, Patrick Bergel, chief executive of Chirp creator Animal Systems, argues that sound is more intuitive and informal.

Since "chirps" carry like speech, he says, we instinctively understand their use and their limitations much as we understand how to participate in a spoken conversation.

Bergel also points out that devices capable of playing and recording sound are both more plentiful and less expensive than gadgets built to use alternatives like NFC, the electronics industry's emerging standard for sharing between devices.

"It's an interesting door opening, this use of sonic signalling - using sound to alert us in a more subtle way than a beep," New Scientists quoted Julian Treasure, chairman of The Sound Agency, an audio design consultancy, as saying.

"There's a little bit of protocol in the real world which is quite important. If you speak to me, we understand that we've entered into a social contract. But sound that you haven't given permission to receive is noise, and generally unwelcome," he said.

Making the chirps sound pleasant took some careful sound design.

According to Animal Systems developer, Dan Jones, the smartphone-generated chirps sound "birdish" rather than birdlike.

Bergel said that while earlier attempts sounded more lifelike "I made a pretty passable wren", test users found them creepy, much as robotic attempts to recreate human behaviour can fall foul of the so-called uncanny valley.

Making them work in practice was another challenge. Sharing needs to work in noisy, social environments and it's easy for a chirp to get drowned out by background noise, particularly in echo-prone spaces like hard-surfaced cafes and bars.

So half of each chirp comprises an error-correcting code that ensures the message is received accurately.